Schema Browser

Find detailed descriptions of the data available in each survey/archive.

The Schema Browser displays an extensive explanation of each type of data product each survey/archive offers, along with any relevant analysis and publication information (see also individual survey documentation for more info). For more information on the schema browser, go to the Schema Browser Documentation. For more information on the data products within the schema browser, go to the team's documentation on Data Central (the link for each survey can be found in the Meta box below).

GAMA
GAMA
name: gama | type: survey | Simon Driver [javascript protected email address] |
PI Simon Driver
Contact [javascript protected email address]
Website GAMA
Documentation GAMA
Remote No

GAMA is a project to exploit the latest generation of ground-based and space-borne survey facilities to study cosmology and galaxy formation and evolution.

At the heart of this project lies the GAMA spectroscopic survey of ~300,000 galaxies down to r < 19.8 mag over ~286 deg2, carried out using the AAOmega multi-object spectrograph on the Anglo-Australian Telescope (AAT) by the GAMA team. This project was awarded 210 nights over 7 years (2008–2014) and the observations are now completed. This survey builds on, and is augmented by, previous spectroscopic surveys such as the Sloan Digital Sky Survey (SDSS), the 2dF Galaxy Redshift Survey(2dFGRS) and the Millennium Galaxy Catalogue (MGC).

Panchromatic Data Release
name: pdr | type: data_release | version 1 |

The GAMA Panchromatic Data Release (PDR) represents the largest panchromatic dataset ever assembled, and comprises 230 deg 2 of imaging with photometry in 21 bands. Details can be found in Driver et. al (2015).

Please note many of the Swarped images are large (~80GB) and the complete dataset amounts to 10TB, all data is available online or as a hard copy on request. We would like to especially thank all the people associated with the GALEX, SDSS, VST, UKIDSS, VISTA, WISE and Herschel facilities and associated teams for the acquisition, provision and assistance which has led to the construction of the GAMA PDR.

Imaging
name: imaging | type: imaging |
Description is not available for Imaging.
GALEX
name: GALEXGALEXMIS | type: facility | version 1 |
Description is not available for GALEX.
FUV
name: FUV | type: band | version 1 |
Description is not available for FUV.
NUV
name: NUV | type: band | version 1 |
Description is not available for NUV.
SDSS
name: SDSS | type: facility | version 1 |
Description is not available for SDSS.
u
name: u | type: band | version 1 |
Description is not available for u.
g
name: g | type: band | version 1 |
Description is not available for g.
r
name: r | type: band | version 1 |
Description is not available for r.
i
name: i | type: band | version 1 |
Description is not available for i.
z
name: z | type: band | version 1 |
Description is not available for z.
VST
name: VSTKiDS | type: facility | version 1 |
Description is not available for VST.
u
name: u | type: band | version 1 |
Description is not available for u.
g
name: g | type: band | version 1 |
Description is not available for g.
r
name: r | type: band | version 1 |
Description is not available for r.
i
name: i | type: band | version 1 |
Description is not available for i.
UKIRT
name: UKIRTUKIDSS | type: facility | version 1 |
Description is not available for UKIRT.
Y
name: Y | type: band | version 1 |
Description is not available for Y.
J
name: J | type: band | version 1 |
Description is not available for J.
H
name: H | type: band | version 1 |
Description is not available for H.
K
name: K | type: band | version 1 |
Description is not available for K.
VISTA
name: VISTAVIKING | type: facility | version 1 |
Description is not available for VISTA.
Z
name: Z | type: band | version 1 |
Description is not available for Z.
Y
name: Y | type: band | version 1 |
Description is not available for Y.
J
name: J | type: band | version 1 |
Description is not available for J.
H
name: H | type: band | version 1 |
Description is not available for H.
Ks
name: K | type: band | version 1 |
Description is not available for Ks.
WISE
name: WISE | type: facility | version 1 |
Description is not available for WISE.
W1
name: W1 | type: band | version 1 |
Description is not available for W1.
W2
name: W2 | type: band | version 1 |
Description is not available for W2.
W3
name: W3 | type: band | version 1 |
Description is not available for W3.
W4
name: W4 | type: band | version 1 |
Description is not available for W4.
Herschel
name: HerschelHATLAS | type: facility | version 1 |
Description is not available for Herschel.
P100
name: P100 | type: band | version 1 |
Description is not available for P100.
P160
name: P160 | type: band | version 1 |
Description is not available for P160.
S250
name: S250 | type: band | version 1 |
Description is not available for S250.
S350
name: S350 | type: band | version 1 |
Description is not available for S350.
S500
name: S500 | type: band | version 1 |
Description is not available for S500.
Data Release 2
name: dr2 | type: data_release | version 2 |

The second GAMA data release (DR2) provides AAT/AAOmega spectra, redshifts and a wealth of ancillary information for 72,225 objects from the first phase of the GAMA survey (2008 - 2010, usually referred to as GAMA I). The DR2 web pages describe the data included in this release, and provide access to an SQL database as well as to the actual data (spectra and catalogues).

If you are using GAMA DR2 data in a publication then please cite the DR2 paper (Liske et al. 2015) and acknowledge GAMA.

Catalogues
name: catalogues | type: catalogues |
Description is not available for Catalogues.
ApMatchedPhotom
name: ApMatchedPhotom | type: group | 2012-04-23 | Mehmet Alpaslan [javascript protected email address] | version v02 |
This DMU provides aperture matched ugrizYJHK photometry.
ApMatchedCat
name: ApMatchedCat | type: table | 2012-04-23 | Mehmet Alpaslan [javascript protected email address] | version v02 |
This table contains r-band aperture matched photometry and other Source Extractor outputs for all GAMA DR2 objects.
ApMatchedPhotom
ApMatchedCat
v02
2012-04-23
Mehmet Alpaslan

This catalogue provides Kron and Petrosian photometry for all GAMA DR2
objects, as well as other Source Extractor outputs for the ugrizYJHK
bands obtained from the v02 mosaics using Source Extractor.

The GAMA mosaics have been constructed by stitching together
individual frames of images taken from the SDSS and UKIDSS LAS surveys
using SWarp, a resampling and co-adding program. There is one mosaic
per band and per GAMA survey region. All frames in the mosaics have
been pre-convolved to a common seeing of 2 arcsec and renormalised.
The pixel scale of these mosaics (and hence of the present catalogue)
is 0.339 arcsec per pixel. The zero-point used throughout is 30 mag.
The mosaics are available on the DR2 file server (swpci* files).

The photometry was obtained by using Source Extractor in matched
aperture mode. In short, this mode allows Source Extractor to fit an
aperture around a possible source in one image, and measure the flux
from another. In the present case, we have fit the apertures to r-band
images and measure the fluxes in all 9 bands. This process was
automated using a wrapper written in R that creates a cutout image of
each source in all 9 bands, each of which is fed into Source Extractor
alongside the master r-band cutout. Where Source Extractor fails to
calculate a magnitude (for whatever reason) the default value returned
is 99. Any nonsense results (negative values for FLUX, BACKGROUND or
FWHM) are caused by Source Extractor failing; in these cases consult
the appropriate FLAGS column to get some indication as to why this is
happening.

Some small areas of the GAMA survey regions are not covered by the
YJHK mosaics because some frames in these bands had to be removed due
to poor image quality. The YJHK magnitudes and errors of objects
located in these areas have been set to -99, while their fluxes and
associated errors have been set to 0 and 1E99, respectively.

#######################################################################

MAG_AUTO_ / MAG_PETRO_

The magnitudes presented in this catalogue have not been corrected for
the effect of foreground Milky Way dust extinction. Should these
corrections be required, they can be obtained from the table
GalacticExtinction in the InputCat DMU.

All photomotry is on the AB system.

#######################################################################

Photometric errors

The errors associated with the MAG_AUTO and MAG_PETRO values have been
calculated and rescaled in such a way as to match the errors used in
the SDSS and UKIDSS photometry catalogues. To do this, the raw Source
Extractor errors have been taken and, for each band, rescaled such
that they match these existing photometry catalogues as accurately as
possible. The original Source Extractor errors are preserved in the
_SE columns.

########################################################################

Potential zero-point offsets

From recent comparisons with VIKING and 2MASS we have discovered an
apparent zero-point offset in our photometry derived from the UKIDSS
LAS data. The cause of this offset is still not fully understood.
This issue will be described in more detail in a future paper
presenting the GAMA II panchromatic photometry catalogue (Driver et
al., in prep.). In the meantime, users may wish to consider applying
the following zero-point offsets to bring the YJHK magnitudes of this
catalogue into agreement with VIKING:

Y_corr = Y_DR2 - 0.13 mag
J_corr = J_DR2 - 0.12 mag
H_corr = H_DR2 - 0.07 mag
K_corr = K_DR2 - 0.11 mag

########################################################################

Dependencies:

InputCat TilingCatv16
Mosaicing v02

#######################################################################

The Source Extractor parameters used to generate this catalogue are as
follows:

DETECT_MINAREA 16
Minimum number of pixels above threshold triggering detection.

DETECT_THRESH 1.7
Detection threshold relative to background.

FILTER N
If true, filtering is applied to the data before extraction.

DEBLEND_NTHRESH 32
Number of deblending sub-thresholds.

DEBLEND_MINCONT 0.00005
Minimum contrast parameter for deblending.

CLEAN_PARAM 0.1
Efficiency of cleaning.

WEIGHT_TYPE NONE
Weighting scheme used for weight maps. In this case, these are not used.

PHOT_FLUXFRAC 0.5
Fraction of flux used to determine each element of the flux radius vector.

SATUR_LEVEL 500000
Pixel value above which the pixel is considered saturated.

MAG_ZEROPOINT 30
Zero-point offset applied to magnitudes.

PIXEL_SCALE 0.339
Pixel scale in arcsec.

For a detailed explanation of what each of these parameters does,
please see this third party guide to Source Extractor.

Address this table as gama_dr2.ApMatchedCat
Name Unit Description UCD (hover for description)
Name Unit Description UCD
ALPHA_J2000 deg RA (r band) pos.eq.ra;em.opt.R
A_IMAGE pixel Profile RMS along major axis (r band) phys.angSize;em.opt.R
BACKGROUND_G counts Background at centroid (g band) instr.background;phot.count;em.opt.G
BACKGROUND_H counts Background at centroid (H band) instr.background;phot.count;em.IR.H
BACKGROUND_I counts Background at centroid (i band) instr.background;phot.count;em.opt.I
BACKGROUND_J counts Background at centroid (J band) instr.background;phot.count;em.IR.J
BACKGROUND_K counts Background at centroid (K band) instr.background;phot.count;em.IR.K
BACKGROUND_R counts Background at centroid (r band) instr.background;phot.count;em.opt.R
BACKGROUND_U counts Background at centroid (u band) instr.background;phot.count;em.opt.U
BACKGROUND_Y counts Background at centroid (Y band) instr.background;phot.count;em.IR.Y
BACKGROUND_Z counts Background at centroid (z band) instr.background;phot.count;em.opt.Z
B_IMAGE pixel Profile RMS along minor axis (r band) phys.angsSize;em.opt.R
CATAID - Unique GAMA object ID meta.id
DEC deg J2000 coordinate pos.eq.dec
DELTA_J2000 deg DEC (r band) pos.eq.dec;em.opt.R
ERRA_IMAGE pixel Major axis profile RMS error (r band) stat.error;phys.angSize;em.opt.R
ERRB_IMAGE pixel Minor axis profile RMS error (r band) stat.error;phys.angSize;em.opt.R
ERRTHETA_J2000 deg J2000 position angle error (r band) stat.error;pos.posAng;em.opt.R
FLAGS_G - Source Extractor flags (g band) meta.code.qual;em.opt.G
FLAGS_H - Source Extractor flags (H band) meta.code.qual;em.IR.H
FLAGS_I - Source Extractor flags (i band) meta.code.qual;em.opt.I
FLAGS_J - Source Extractor flags (J band) meta.code.qual;em.IR.J
FLAGS_K - Source Extractor flags (K band) mag.code.qual;em.IR.K
FLAGS_R - Source Extractor flags (r band) meta.code.qual;em.opt.R
FLAGS_U - Source Extractor flags (u band) meta.code.qual;em.opt.U
FLAGS_Y - Source Extractor flags (Y band) meta.code.qual;em.IR.Y
FLAGS_Z - Source Extractor flags (z band) meta.code.qual;em.opt.Z
FLUXERR_AUTO_G counts Kron flux error (g band) stat.error;phot.flux;em.opt.G
FLUXERR_AUTO_H counts Kron flux error (H band) stat.error;phot.flux;em.IR.H
FLUXERR_AUTO_I counts Kron flux error (i band) stat.error;phot.flux;em.opt.I
FLUXERR_AUTO_J count Kron flux error (J band) stat.error;phot.flux;em.IR.J
FLUXERR_AUTO_K counts Kron flux error (K band) stat.error;phot.flux;em.IR.K
FLUXERR_AUTO_R counts Kron flux error (r band) stat.error;phot.flux;em.opt.R
FLUXERR_AUTO_U counts Kron flux error (u band) stat.error;phot.flux;em.opt.U
FLUXERR_AUTO_Y counts Kron flux error (Y band) stat.error;phot.flux;em.IR.Y
FLUXERR_AUTO_Z counts Kron flux error (z band) stat.error;phot.flux;em.opt.Z
FLUXERR_PETRO_G counts Petrosian flux error (g band) stat.error;phot.flux;em.opt.G
FLUXERR_PETRO_H counts Petrosian flux error (H band) stat.error;phot.flux;em.IR.H
FLUXERR_PETRO_I counts Petrosian flux error (i band) stat.error;phot.flux;em.opt.I
FLUXERR_PETRO_J count Petrosian flux error (J band) stat.error;phot.flux;em.IR.J
FLUXERR_PETRO_K counts Petrosian flux error (K band) stat.error;phot.flux;em.IR.K
FLUXERR_PETRO_R counts Petrosian flux error (r band) stat.error;phot.flux;em.opt.R
FLUXERR_PETRO_U counts Petrosian flux error (u band) stat.error;phot.flux;em.opt.U
FLUXERR_PETRO_Y counts Petrosian flux error (Y band) stat.error;phot.flux;em.IR.Y
FLUXERR_PETRO_Z counts Petrosian flux error (z band) stat.error;phot.flux;em.opt.Z
FLUX_AUTO_G counts Kron flux (g band) phot.flux;em.opt.G
FLUX_AUTO_H counts Kron flux (H band) phot.flux;em.IR.H
FLUX_AUTO_I counts Kron flux (i band) phot.flux;em.opt.I
FLUX_AUTO_J count Kron flux (J band) phot.flux;em.IR.J
FLUX_AUTO_K counts Kron flux (K band) phot.flux;em.IR.K
FLUX_AUTO_R counts Kron flux (r band) phot.flux;em.opt.R
FLUX_AUTO_U counts Kron flux (u band) phot.flux;em.opt.U
FLUX_AUTO_Y counts Kron flux (Y band) phot.flux;em.IR.Y
FLUX_AUTO_Z counts Kron flux (z band) phot.flux;em.opt.Z
FLUX_MAX_G counts Peak flux (g band) phot.flux;stat.max;em.opt.G
FLUX_MAX_H counts Peak flux (H band) phot.flux;stat.max;em.IR.H
FLUX_MAX_I counts Peak flux (i band) phot.flux;stat.max;em.opt.I
FLUX_MAX_J counts Peak flux (J band) phot.flux;stat.max;em.IR.J
FLUX_MAX_K counts Peak flux (K band) phot.flux;stat.max;em.IR.K
FLUX_MAX_R counts Peak flux (r band) phot.flux;stat.max;em.opt.R
FLUX_MAX_U counts Peak flux (u band) phot.flux;stat.max;em.opt.U
FLUX_MAX_Y counts Peak flux (Y band) phot.flux;stat.max;em.IR.Y
FLUX_MAX_Z count Peak flux (z band) phot.flux;stat.max;em.opt.Z
FLUX_PETRO_G counts Petrosian flux (g band) phot.flux;em.opt.G
FLUX_PETRO_H counts Petrosian flux (H band) phot.flux;em.IR.H
FLUX_PETRO_I counts Petrosian flux (i band) phot.flux;em.opt.I
FLUX_PETRO_J count Petrosian flux (J band) phot.flux;em.IR.J
FLUX_PETRO_K counts Petrosian flux (K band) phot.flux;em.IR.K
FLUX_PETRO_R counts Petrosian flux (r band) phot.flux;em.opt.R
FLUX_PETRO_U counts Petrosian flux (u band) phot.flux;em.opt.U
FLUX_PETRO_Y counts Petrosian flux (Y band) phot.flux;em.IR.Y
FLUX_PETRO_Z counts Petrosian flux (z band) phot.flux;em.opt.Z
FWHM_IMAGE_G pixel FWHM assuming a Gaussian core (g band) spect.line.width;obs.image;em.opt.G
FWHM_IMAGE_H pixel FWHM assuming a Gaussian core (H band) spect.line.width;obs.image;em.IR.H
FWHM_IMAGE_I pixel FWHM assuming a Gaussian core (i band) spect.line.width;obs.image;em.opt.I
FWHM_IMAGE_J pixel FWHM assuming a Gaussian core (J band) spect.line.width;obs.image;em.IR.J
FWHM_IMAGE_K pixel FWHM assuming a Gaussian core (K band) spect.line.width;obs.image;em.IR.K
FWHM_IMAGE_R pixel FWHM assuming a Gaussian core (r band) spect.line.width;obs.image;em.opt.R
FWHM_IMAGE_U pixel FWHM assuming a Gaussian core (u band) spect.line.width;obs.image;em.opt.U
FWHM_IMAGE_Y pixel FWHM assuming a Gaussian core (Y band) spect.line.width;obs.image;em.IR.Y
FWHM_IMAGE_Z pixel FWHM assuming a Gaussian core (z band) spect.line.width;obs.image;em.opt.Z
ISOAREAF_IMAGE pixel Isophotal area (filtered) (r band) phys.angArea;em.opt.R
ISOAREA_IMAGE_G pixel Isophotal area (g band) phys.angArea;em.opt.G
ISOAREA_IMAGE_H pixel Isophotal area (H band) phys.angArea;em.IR.H
ISOAREA_IMAGE_I pixel Isophotal area (i band) phys.angArea;em.opt.I
ISOAREA_IMAGE_J pixel Isophotal area (J band) phys.angArea;em.IR.J
ISOAREA_IMAGE_K pixel Isophotal area (K band) phys.angArea;em.IR.K
ISOAREA_IMAGE_R pixel Isophotal area (r band) phys.angArea;em.opt.R
ISOAREA_IMAGE_U pixel Isophotal area (u band) phys.angArea;em.opt.U
ISOAREA_IMAGE_Y pixel Isophotal area (Y band) phys.angArea;em.IR.Y
ISOAREA_IMAGE_Z pixel Isophotal area (z band) phys.angArea;em.opt.Z
KRON_RADIUS pixel Kron radius (r band) phys.size.radius;em.opt.R
MAGERR_AUTO_G mag Kron magnitude error (g band) stat.error;phot.mag;em.opt.G
MAGERR_AUTO_H mag Kron magnitude error (H band) stat.error;phot.mag;em.IR.H
MAGERR_AUTO_I mag Kron magnitude error (i band) stat.error;phot.mag;em.opt.I
MAGERR_AUTO_J mag Kron magnitude error (J band) stat.error;phot.mag;em.IR.J
MAGERR_AUTO_K mag Kron magnitude error (K band) stat.error;phot.mag;em.IR.K
MAGERR_AUTO_R mag Kron magnitude (r band) stat.error;phot.mag;em.opt.R
MAGERR_AUTO_U mag Kron magnitude error (u band) stat.error;phot.mag;em.opt.U
MAGERR_AUTO_Y mag Kron magnitude error (Y band) stat.error;phot.mag;em.IR.Y
MAGERR_AUTO_Z mag Kron magnitude error (z band) stat.error;phot.mag;em.opt.Z
MAGERR_PETRO_G mag Petrosian magnitude (g band) stat.error;phot.mag;em.opt.G
MAGERR_PETRO_H mag Petrosian magnitude error (H band) stat.error;phot.mag;em.IR.H
MAGERR_PETRO_I mag Petrosian magnitude error (i band) stat.error;phot.mag;em.opt.I
MAGERR_PETRO_J mag Petrosian magnitude error (J band) stat.error;phot.mag;em.IR.J
MAGERR_PETRO_K mag Petrosian magnitude error (K band) stat.error;phot.mag;em.IR.K
MAGERR_PETRO_R mag Petrosian magnitude (r band) stat.error;phot.mag;em.opt.R
MAGERR_PETRO_U mag Petrosian magnitude error (u band) stat.error;phot.mag;em.opt.U
MAGERR_PETRO_Y mag Petrosian magnitude error (Y band) stat.error;phot.mag;em.IR.Y
MAGERR_PETRO_Z mag Petrosian magnitude error (z band) stat.error;phot.mag;em.opt.Z
MAG_AUTO_G mag Kron magnitude (g band) phot.mag;em.opt.G
MAG_AUTO_H mag Kron magnitude (H band) phot.mag;em.IR.H
MAG_AUTO_I mag Kron magntiude (i band) phot.mag;em.opt.I
MAG_AUTO_J mag Kron magnitude (J band) phot.mag;em.IR.J
MAG_AUTO_K mag Kron magintude (K band) phot.mag;em.IR.K
MAG_AUTO_R mag Kron magnitude (r band) phot.mag;em.opt.R
MAG_AUTO_U mag Kron magnitude (u band) phot.mag;em.opt.U
MAG_AUTO_Y mag Kron magnitude (Y band) phot.mag;em.IR.Y
MAG_AUTO_Z mag Kron magnitude (z band) phot.mag.em.opt.Z
MAG_PETRO_G mag Petrosian magnitude (g band) phot.mag;em.opt.G
MAG_PETRO_H mag Petrosian magnitude (H band) phot.mag;em.IR.H
MAG_PETRO_I mag Petrosian magnitude (i band) phot.mag;em.opt.I
MAG_PETRO_J mag Petrosian magnitude (J band) phot.mag;em.IR.J
MAG_PETRO_K mag Petrosian magnitude (K band) phot.mag;em.IR.K
MAG_PETRO_R mag Petrosian magnitude (r band) phot.mag;em.opt.R
MAG_PETRO_U mag Petrosian magnitude (u band) phot.mag;em.opt.U
MAG_PETRO_Y mag Petrosian magnitude (Y band) phot.mag;em.IR.Y
MAG_PETRO_Z mag Petrosian magnitude (z band) phot.mag;em.opt.Z
MU_MAX_G mag/arcsec^2 Peak surface brightness (g band) phot.mag.sb;stat.max;em.opt.G
MU_MAX_H mag/arcsec^2 Peak surface brightness (H band) phot.mag.sb;stat.max;em.IR.H
MU_MAX_I mag/arcsec^2 Peak surface brightness (i band) phot.mag.sb;stat.max;em.opt.I
MU_MAX_J mag/arcsec^2 Peak surface brightness (J band) phot.mag.sb;stat.max;em.IR.J
MU_MAX_K mag/arcsec^2 Peak surface brightness (K band) phot.mag.sb;stat.max;em.IR.K
MU_MAX_R mag/arcsec^2 Peak surface brightness (r band) phot.mag.sb;stat.max;em.opt.R
MU_MAX_U mag/arcsec^2 Peak surface brightness (u band) phot.mag.sb;stat.max;em.opt.U
MU_MAX_Y mag/arcsec^2 Peak surface brightness (Y band) phot.mag.sb;stat.max;em.IR.Y
MU_MAX_Z mag/arcsec^2 Peak surface brightness (z band) phot.mag.sb;statm.ax;em.opt.Z
MU_THRESHOLD mag/arcsec^2 Detection threshold above background (r band) instr.sensitivity;phot.mag.sb;em.opt.R
OBJID - SDSS objid meta.id
PETRO_RADIUS pixel Petrosian radius (r band) phys.size.radius;em.opt.R
RA deg J2000 coordinate pos.eq.ra
THETA_IMAGE deg Position angle (counterclockwise) pos.posAng;em.opt.R
THETA_J2000 deg Position angle (east of north) pos.posAng;em.opt.R
THRESHOLD counts Detection threshold above background (r band) instr.sensitivity;phot.count;em.opt.R
X pixel x coordinate of aperture centre in r band cutout pos
Y pixel y coordinate of aperture centre in r band cutout pos
EnvironmentMeasures
name: EnvironmentMeasures | type: group | 2014-08-21 | Sarah Brough [javascript protected email address] | version v02 |
This DMU provides several different metrics of the local environment of GAMA DR2 galaxies: a surface density, the number of galaxies within a cylinder, and the density of galaxies within an adaptive Gaussian ellipsoid.
EnvironmentMeasures
EnvironmentMeasures
v02
2014-08-21
Sarah Brough

The EnvironmentMeasures DMU provides several different metrics of the
local environment of GAMA DR2 galaxies: a surface density, the number
of galaxies within a cylinder, and the density of galaxies within an
adaptive Gaussian ellipsoid.

Note that this release only covers the GAMA G15 survey region.

All of these environment measurements are performed on a density
defining pseudo-volume-limited population of galaxies. This population
is defined as all galaxies with M_r(z_ref=0, Q=0.78) < -20.4 mag,
where Q defines the expected evolution of M_r as a function of
redshift. Q is taken from Loveday et al. (2014, in prep). Given the
depth of the GAMA I survey (r < 19.4 mag) the above absolute magnitude
limit implies a redshift (i.e. volume) limit of z=0.18333. However, in
order to account for the upper edge of the velocity range employed
when searching for nearby galaxies (see below), the environment
measurements are only provided for galaxies out to z=0.18. The exact
sample included in this DMU is: all GAMA DR2 galaxies in G15 with
redshift quality nQ > 2 (i.e. reliable redshifts) and within the
redshift limits of 0.002 < Z_TONRY <= 0.18.

This catalogue is based on DistancesFrames (which is itself based on
TilingCat), kCorrections and the GAMA I final completeness masks, and
uses H_0 = 70 km/s/Mpc, O_M = 0.3, O_L = 0.7.

#######################################################################

IMPORTANT NOTE:

On 2014-09-03 this DMU was upgraded from v01 to v02 following the
discovery of two bugs in v01. In v01 the faint limit of the density
defining population was incorrectly set to -20 mag. It has now been
set to the correct value of -20.4 mag. There was also a bug in the
flagging of galaxies. We furthermore took the opportunity to update
the value of Q from 0.87 (v01) to 0.78 (v02).

#######################################################################

We now describe the three environment measures provided by this DMU in
more detail.

SurfaceDensity:
This column provides the surface density based on the distance to the
5th nearest neighbour among the density defining population in a
velocity cylinder of +/-1000 km/s, i.e. 5 / (Pi * DistanceTo5nn^2).

CountInCyl:
This column provides the number of (other) galaxies from the density
defining population within a cylinder of co-moving radius 1 Mpc and a
velocity range of +/-1000 km/s. The overdensity is given by
CountInCyl / (nbar_ref * volume_of_cylinder)
where nbar_ref = 0.00703 Mpc^-3 is the average number density of the
density defining population.

AGEDensity:
This column provides the density of galaxies from the density defining
population in an adaptive Gaussian ellipsoid defined by
(r_a/(3*sigma))^2 + (r_z/(3*AGEScale*sigma))^2 <= 1, where r_a and r_z
are the distances from the centre in the plane of sky and along the
line-of-sight in co-moving Mpc, respectively, and sigma = 2 Mpc. The
adaptive scaling factor, AGEScale = 1 + (0.2*n_gals_within_2Mpc), is
used to scale the value of sigma along the redshift axis by up to a
factor of 3 (i.e. n_gals_within_2Mpc[max]=10) for the highest density
environments to compensate for the "finger-of-God" effect (Schawinski
et al. (2007)
, Thomas et al. (2010)).

#######################################################################

All unflagged environment measures are corrected for survey
incompleteness as (for example):
SurfaceDensity = SurfaceDensity_raw * (1 / Completeness),
where Completeness is the local completeness as given by the
completeness mask at the position of the galaxy, and not a completeness
averaged over the area or volume over which the environment measure is
determined.

#######################################################################

The errors on the environment measures are calculated as follows.

SurfaceDensityErr:
Calculated as the larger of
|(SurfaceDensity to 5th nearest neighbour) -
(SurfaceDensity to 4th nearest neighbour)|
and
|(SurfaceDensity to 5th nearest neighbour) -
(SurfaceDensity to 6th nearest neighbour)|

CountInCylErr:
Calculated as sqrt(CountInCyl).

AGEErr:
Calculated as sqrt(Ngals).
Note that this is the Poisson error on the number of galaxies found in
the adaptive Gaussian ellipsoid. It is *not* the error on AGEDensity.

#######################################################################

Below we describe the meanings of the various problem-indicating flags.

SurfaceDensityFlag:

Flag value Flag meaning
------------------------------------------------------------------
0 SurfaceDensity is exact.
1 The distance to the 5th nearest neighbour is larger
than the distance to the nearest angular survey
edge, but a nearer galaxy is within this distance.
The surface density is calculated using the
distance to the nearer galaxy and hence
SurfaceDensity is an upper limit.
2 No neighbours found among the density defining
population within the distance to the nearest
angular survey edge. SurfaceDensity is calculated
as 1 / (Pi * DistanceToEdge^2).
4 The galaxy lies inside a bright star exclusion
region (Completeness=-1) or outside of the GAMA
survey boundary (as defined by the completeness
mask, Completeness=-2). SurfaceDensity cannot be
determined accurately and is set to -999.9.


CountInCylFlag:

Flag value Flag meaning
------------------------------------------------------------------
0 CountInCyl is exact.
1 The cylinder extends across the nearest angular
survey edge. CountInCyl is a lower limit.
2 The galaxy lies inside a bright star exclusion
region (Completeness=-1) or outside of the GAMA
survey boundary (as defined by the completeness
mask, Completeness=-2). CountInCyl cannot be
determined accurately and is set to -999.9.


AGEDensityFlag:

Flag value Flag meaning
------------------------------------------------------------------
0 AGEDensity is exact.
1 The ellipsoid extends across the nearest angular
survey edge. AGEDensity is set to -999.9.
2 No (other) galaxies from the density defining
population are found within the ellipsoid (not due
to angular survey edge). AGEDensity is set to
-999.9.
4 The galaxy lies inside a bright star exclusion
region (Completeness=-1) or outside of the GAMA
survey boundary (as defined by the completeness
mask, Completeness=-2). AGEDensity cannot be
determined accurately and is set to -999.9.

#######################################################################

M_r:
Calculated as R_PETRO - Dmod70 - KCOR_(r,zref=0).

EnvironmentMeasures
name: EnvironmentMeasures | type: table | 2014-08-21 | Sarah Brough [javascript protected email address] | version v02 |
This catalogue provides three different environment measures for all GAMA DR2 galaxies in G15 with 0.002 < z < 0.18: a surface density, the number of galaxies within a cylinder, and the density of galaxies within an adaptive Gaussian ellipsoid.
EnvironmentMeasures
EnvironmentMeasures
v02
2014-08-21
Sarah Brough

The EnvironmentMeasures DMU provides several different metrics of the
local environment of GAMA DR2 galaxies: a surface density, the number
of galaxies within a cylinder, and the density of galaxies within an
adaptive Gaussian ellipsoid.

Note that this release only covers the GAMA G15 survey region.

All of these environment measurements are performed on a density
defining pseudo-volume-limited population of galaxies. This population
is defined as all galaxies with M_r(z_ref=0, Q=0.78) < -20.4 mag,
where Q defines the expected evolution of M_r as a function of
redshift. Q is taken from Loveday et al. (2014, in prep). Given the
depth of the GAMA I survey (r < 19.4 mag) the above absolute magnitude
limit implies a redshift (i.e. volume) limit of z=0.18333. However, in
order to account for the upper edge of the velocity range employed
when searching for nearby galaxies (see below), the environment
measurements are only provided for galaxies out to z=0.18. The exact
sample included in this DMU is: all GAMA DR2 galaxies in G15 with
redshift quality nQ > 2 (i.e. reliable redshifts) and within the
redshift limits of 0.002 < Z_TONRY <= 0.18.

This catalogue is based on DistancesFrames (which is itself based on
TilingCat), kCorrections and the GAMA I final completeness masks, and
uses H_0 = 70 km/s/Mpc, O_M = 0.3, O_L = 0.7.

#######################################################################

IMPORTANT NOTE:

On 2014-09-03 this DMU was upgraded from v01 to v02 following the
discovery of two bugs in v01. In v01 the faint limit of the density
defining population was incorrectly set to -20 mag. It has now been
set to the correct value of -20.4 mag. There was also a bug in the
flagging of galaxies. We furthermore took the opportunity to update
the value of Q from 0.87 (v01) to 0.78 (v02).

#######################################################################

We now describe the three environment measures provided by this DMU in
more detail.

SurfaceDensity:
This column provides the surface density based on the distance to the
5th nearest neighbour among the density defining population in a
velocity cylinder of +/-1000 km/s, i.e. 5 / (Pi * DistanceTo5nn^2).

CountInCyl:
This column provides the number of (other) galaxies from the density
defining population within a cylinder of co-moving radius 1 Mpc and a
velocity range of +/-1000 km/s. The overdensity is given by
CountInCyl / (nbar_ref * volume_of_cylinder)
where nbar_ref = 0.00703 Mpc^-3 is the average number density of the
density defining population.

AGEDensity:
This column provides the density of galaxies from the density defining
population in an adaptive Gaussian ellipsoid defined by
(r_a/(3*sigma))^2 + (r_z/(3*AGEScale*sigma))^2 <= 1, where r_a and r_z
are the distances from the centre in the plane of sky and along the
line-of-sight in co-moving Mpc, respectively, and sigma = 2 Mpc. The
adaptive scaling factor, AGEScale = 1 + (0.2*n_gals_within_2Mpc), is
used to scale the value of sigma along the redshift axis by up to a
factor of 3 (i.e. n_gals_within_2Mpc[max]=10) for the highest density
environments to compensate for the "finger-of-God" effect (Schawinski
et al. (2007)
, Thomas et al. (2010)).

#######################################################################

All unflagged environment measures are corrected for survey
incompleteness as (for example):
SurfaceDensity = SurfaceDensity_raw * (1 / Completeness),
where Completeness is the local completeness as given by the
completeness mask at the position of the galaxy, and not a completeness
averaged over the area or volume over which the environment measure is
determined.

#######################################################################

The errors on the environment measures are calculated as follows.

SurfaceDensityErr:
Calculated as the larger of
|(SurfaceDensity to 5th nearest neighbour) -
(SurfaceDensity to 4th nearest neighbour)|
and
|(SurfaceDensity to 5th nearest neighbour) -
(SurfaceDensity to 6th nearest neighbour)|

CountInCylErr:
Calculated as sqrt(CountInCyl).

AGEErr:
Calculated as sqrt(Ngals).
Note that this is the Poisson error on the number of galaxies found in
the adaptive Gaussian ellipsoid. It is *not* the error on AGEDensity.

#######################################################################

Below we describe the meanings of the various problem-indicating flags.

SurfaceDensityFlag:

Flag value Flag meaning
------------------------------------------------------------------
0 SurfaceDensity is exact.
1 The distance to the 5th nearest neighbour is larger
than the distance to the nearest angular survey
edge, but a nearer galaxy is within this distance.
The surface density is calculated using the
distance to the nearer galaxy and hence
SurfaceDensity is an upper limit.
2 No neighbours found among the density defining
population within the distance to the nearest
angular survey edge. SurfaceDensity is calculated
as 1 / (Pi * DistanceToEdge^2).
4 The galaxy lies inside a bright star exclusion
region (Completeness=-1) or outside of the GAMA
survey boundary (as defined by the completeness
mask, Completeness=-2). SurfaceDensity cannot be
determined accurately and is set to -999.9.


CountInCylFlag:

Flag value Flag meaning
------------------------------------------------------------------
0 CountInCyl is exact.
1 The cylinder extends across the nearest angular
survey edge. CountInCyl is a lower limit.
2 The galaxy lies inside a bright star exclusion
region (Completeness=-1) or outside of the GAMA
survey boundary (as defined by the completeness
mask, Completeness=-2). CountInCyl cannot be
determined accurately and is set to -999.9.


AGEDensityFlag:

Flag value Flag meaning
------------------------------------------------------------------
0 AGEDensity is exact.
1 The ellipsoid extends across the nearest angular
survey edge. AGEDensity is set to -999.9.
2 No (other) galaxies from the density defining
population are found within the ellipsoid (not due
to angular survey edge). AGEDensity is set to
-999.9.
4 The galaxy lies inside a bright star exclusion
region (Completeness=-1) or outside of the GAMA
survey boundary (as defined by the completeness
mask, Completeness=-2). AGEDensity cannot be
determined accurately and is set to -999.9.

#######################################################################

M_r:
Calculated as R_PETRO - Dmod70 - KCOR_(r,zref=0).

Address this table as gama_dr2.EnvironmentMeasures
Name Unit Description UCD (hover for description)
Name Unit Description UCD
AGEDensity Mpc^-3 Density of galaxies within an adaptive Gaussian ellipsoid src.density
AGEDensityFlag - Flag indicating problems with AGEDensity, see notes meta.code.error;src.density
AGEErr - Poisson error on the number of galaxies used to calculate AGEDensity src.density;stat.error
AGEScale - Adaptive scaling factor for adaptive Gaussian ellipsoid arith.factor
CATAID - Unique GAMA ID meta.id
Completeness - Value used to correct environment measures for local survey incompleteness (see notes) arith.factor
CountInCyl - Number of (other) galaxies within cylinder of radius 1 co-moving Mpc src.density
CountInCylErr - Poisson error on number of galaxies in cylinder stat.error;src.density
CountInCylFlag - Flag indicating problems with CountInCyl (see notes) meta.code.error;src.density
DEC deg J2000 pos.eq.dec
DistanceTo5nn Mpc Distance to 5th nearest neighbour in co-moving units pos.distance
DistanceToEdge Mpc Distance to nearest angular survey edge in co-moving units pos.distance
M_r mag Extinction and k-corrected absolute r-band magnitude phys.magAbs
RA deg J2000 pos.eq.ra
SurfaceDensity Mpc^-2 Surface density based on the distance to the 5th nearest neighbour src.density
SurfaceDensityErr Mpc^-2 Surface density uncertainty src.density;stat.error
SurfaceDensityFlag - Flag indicating problems with surface density measurement (see notes) meta.code.error;src.density
Z_TONRY - Heliocentric redshift corrected for the effects of peculiar velocity src.redshift
nQ - Redshift quality flag meta.code.qual;src.redshift
ExternalSpec
name: ExternalSpec | type: group | 2011-03-03 | Joe Liske [javascript protected email address] | version v01 |
This DMU collects spectra for GAMA DR2 objects from previous spectroscopic surveys such as the SDSS.
ExternalSpec
2011-03-03
Joe Liske

The ExternalSpec DMU collects spectra of GAMA DR2 objects from
existing spectroscopic surveys. The spectra were taken from the
following surveys:

Survey # of spectra
------------------------------------------------
SDSS DR7 16267
2dFGRS Final data release 11906
2QZ Final data release 150
MGC Final data release 2154
2SLAQ-LRG Final data release 44
2SLAQ-QSO Final data release 43
WiggleZ DR1 16
6dFGS Final data release 248
------------------------------------------------
Total 30828

Duplicate observations have been included (except in the case of
WiggleZ). The spectra are provided as 1D fits files and are available
from the GAMA DR2 fileserver in the directory spectra/. The files are
essentially those that are provided by the various surveys, except
that multiple extensions (sometimes used to store duplicate
observations) are extracted to individual files. For each spectrum we
have also added its entry from the ExternalSpecAll table (see below)
to the fits header. In case of conflicts with existing keywords, these
were first renamed.

See the directory descriptions for the various survey data on the GAMA
fileserver for more details.

-----------------------------------------------------------------------

Apart from the spectra, this DMU also produces the table
ExternalSpecAll, which lists all of the available external spectra
(including all duplicate observations) as well as their redshifts as
determined by the originating surveys. In addition, the table
ExternalSpec is provided, which lists only the those external spectra
that provide the best redshifts for GAMA DR2 objects. Both are in the
same format and the latter is an exact subset of the former. In fact,
ExternalSpec is a "view" of ExternalSpecAll. It lists only those
entries with IS_SBEST = TRUE, meaning that it excludes intra-survey
duplicate observations. However, it still includes inter-survey
duplications.

In the following we provide additional information for some of the
parameters in these tables:

SPECID:
-------
This is the spectrum's unique identifier as used in the GAMA DR2
database. The value of this parameter depends on the orginating survey
of the spectrum:

SDSS: specObjID
2dFGRS: "2dF"SEQNUM (+ _n for duplications, where n=2,3,4)
2QZ: "2QZ"IAUNAMEx (where x=a,b,c,d,e,f)
MGC: "MGC"ID (+ _n for duplications, where n=2,3,4,5)
2SLAQ-LRG: "2SL"IAUNAME_n (where n=1,2,3,4)
2SLAQ-QSO: "2SL"IAUNAME_FLD_DATE
WiggleZ: "W"n (where n is a multi-digit number taken from the file name)
6dFGS: "6dF"TARGETNAME (+ _n for duplications, n=2)


nQ:
---
This is a redshift quality flag. We have attempted to translate the
redshift qualities of the various surveys to the GAMA system (nQ =
0-4, with nQ >= 3 used for science):

SDSS:
nQ = 1 + (zconf > 0.2) + (zwarning_ok && zconf > 0.7) +
(zconf > 0.9) + (zconf > 0.99)
where zwarning_ok is 1 if there are no absorption or emission line
redshift inconsistencies and the 4000 A break is not too large.
Note that in the case of the SDSS we allow nQ = 5 because of the
exceptional reliability of these redshifts.

2dFGRS:
If QUALITY = 5 then nQ = 4, else nQ = QUALITY.

2QZ:
nQ QUALTHIS
-------------------
3 11
2 12,21,22
1 23,33

MGC:
If Z_QUAL = 5 then nQ = 4, else nQ = Z_QUAL.

2SLAQ-LRG:
If qop >= 3 then nQ = 3, else nQ = qop.

2SLAQ-QSO:
nQ qual
-------------------
3 11
2 12,21,22
1 23,33

WiggleZ:
If Qop >= 3 then nQ = 3, else nQ = Qop.

6dFGS:
If QUALITY >= 3 then nQ = 3, else nQ = QUALITY.


PROB:
-----
This parameter is set to zconf for spectra from the SDSS, and to 0 in
all other cases.


CATAID / GAMA_NAME:
-------------------
These parameters identify the GAMA object the spectrum was matched to.
For a given spectrum a matching GAMA object was identified by finding
the spectrum's closest GAMA object (within 2 arcsec) in the catalogue
resulting from the union of TilingCat and SpStandards from the
InputCat DMU.


IC_FLAG:
--------
This is a bitwise flag identifying the catalogue(s) in which the
matched GAMA object was found:

Bit n 2^(n-1) Catalogue
------------------------------
1 1 InputCatA
2 2 TilingCat
3 4 SpStandards


DIST:
-----
Distance between the spectrum and the matched GAMA object in arcsec.


IS_SBEST:
---------
In cases where multiple spectra from a given survey were matched to
the same GAMA object this flag identifies the spectrum that provides
the best redshift for that object.

SDSS:
The spectrum providing the best redshift was identified by first
considering only sciencePrimary spectra with nQ >= 3 and within 1
arcsec of the object. If there were multiple, then we selected the one
with the highest nQ value. If there were multiple with the same nQ
value, we selected the closest spectrum. In cases without any nQ >= 3
sciencePrimary spectra within 1 arcsec we simply selected first by nQ,
then by distance.

All other surveys:
The spectrum providing the best redshift was selected first by nQ, and
then (in cases of multiple spectra with the same nQ) by distance
between the object and the spectrum.

-----------------------------------------------------------------------

This DMU also provides the table ExternalzAll which contains a
relatively small number of redshifts from various literature sources,
where the original spectra from which these redshifts were measured
are not available to GAMA.

Redshifts have been collected from the following sources:

Survey # of redshifts Source
---------------------------------------------------------------------
NED 3 NED website
Updated Zwicky Catalog 214 VizieR: J/PASP/111/438
---------------------------------------------------------------------
Total 217

All redshifts were matched to GAMA objects in the same way as the
spectra above.


SPECID:
-------
NED: "NED_"common_name
UZC: "UZC"serial_number


nQ and PROB:
------------
NED: nQ = 3
PROB = 0.0
UZC: nQ = 3 if UZC_class = 0 or 1, else nQ = 2
PROB = 0.0

ExternalSpec
name: ExternalSpec | type: table | 2011-03-03 | Joe Liske [javascript protected email address] | version v01 |
This table lists those spectra from previous spectroscopic surveys (such as the SDSS) that provide the best redshifts for GAMA DR2 objects. This table is an exact subset of the table ExternalSpecAll. It lists only those entries with IS_SBEST = TRUE, meaning that it excludes intra-survey duplicate observations. However, it still includes inter-survey duplications.
ExternalSpec
2011-03-03
Joe Liske

The ExternalSpec DMU collects spectra of GAMA DR2 objects from
existing spectroscopic surveys. The spectra were taken from the
following surveys:

Survey # of spectra
------------------------------------------------
SDSS DR7 16267
2dFGRS Final data release 11906
2QZ Final data release 150
MGC Final data release 2154
2SLAQ-LRG Final data release 44
2SLAQ-QSO Final data release 43
WiggleZ DR1 16
6dFGS Final data release 248
------------------------------------------------
Total 30828

Duplicate observations have been included (except in the case of
WiggleZ). The spectra are provided as 1D fits files and are available
from the GAMA DR2 fileserver in the directory spectra/. The files are
essentially those that are provided by the various surveys, except
that multiple extensions (sometimes used to store duplicate
observations) are extracted to individual files. For each spectrum we
have also added its entry from the ExternalSpecAll table (see below)
to the fits header. In case of conflicts with existing keywords, these
were first renamed.

See the directory descriptions for the various survey data on the GAMA
fileserver for more details.

-----------------------------------------------------------------------

Apart from the spectra, this DMU also produces the table
ExternalSpecAll, which lists all of the available external spectra
(including all duplicate observations) as well as their redshifts as
determined by the originating surveys. In addition, the table
ExternalSpec is provided, which lists only the those external spectra
that provide the best redshifts for GAMA DR2 objects. Both are in the
same format and the latter is an exact subset of the former. In fact,
ExternalSpec is a "view" of ExternalSpecAll. It lists only those
entries with IS_SBEST = TRUE, meaning that it excludes intra-survey
duplicate observations. However, it still includes inter-survey
duplications.

In the following we provide additional information for some of the
parameters in these tables:

SPECID:
-------
This is the spectrum's unique identifier as used in the GAMA DR2
database. The value of this parameter depends on the orginating survey
of the spectrum:

SDSS: specObjID
2dFGRS: "2dF"SEQNUM (+ _n for duplications, where n=2,3,4)
2QZ: "2QZ"IAUNAMEx (where x=a,b,c,d,e,f)
MGC: "MGC"ID (+ _n for duplications, where n=2,3,4,5)
2SLAQ-LRG: "2SL"IAUNAME_n (where n=1,2,3,4)
2SLAQ-QSO: "2SL"IAUNAME_FLD_DATE
WiggleZ: "W"n (where n is a multi-digit number taken from the file name)
6dFGS: "6dF"TARGETNAME (+ _n for duplications, n=2)


nQ:
---
This is a redshift quality flag. We have attempted to translate the
redshift qualities of the various surveys to the GAMA system (nQ =
0-4, with nQ >= 3 used for science):

SDSS:
nQ = 1 + (zconf > 0.2) + (zwarning_ok && zconf > 0.7) +
(zconf > 0.9) + (zconf > 0.99)
where zwarning_ok is 1 if there are no absorption or emission line
redshift inconsistencies and the 4000 A break is not too large.
Note that in the case of the SDSS we allow nQ = 5 because of the
exceptional reliability of these redshifts.

2dFGRS:
If QUALITY = 5 then nQ = 4, else nQ = QUALITY.

2QZ:
nQ QUALTHIS
-------------------
3 11
2 12,21,22
1 23,33

MGC:
If Z_QUAL = 5 then nQ = 4, else nQ = Z_QUAL.

2SLAQ-LRG:
If qop >= 3 then nQ = 3, else nQ = qop.

2SLAQ-QSO:
nQ qual
-------------------
3 11
2 12,21,22
1 23,33

WiggleZ:
If Qop >= 3 then nQ = 3, else nQ = Qop.

6dFGS:
If QUALITY >= 3 then nQ = 3, else nQ = QUALITY.


PROB:
-----
This parameter is set to zconf for spectra from the SDSS, and to 0 in
all other cases.


CATAID / GAMA_NAME:
-------------------
These parameters identify the GAMA object the spectrum was matched to.
For a given spectrum a matching GAMA object was identified by finding
the spectrum's closest GAMA object (within 2 arcsec) in the catalogue
resulting from the union of TilingCat and SpStandards from the
InputCat DMU.


IC_FLAG:
--------
This is a bitwise flag identifying the catalogue(s) in which the
matched GAMA object was found:

Bit n 2^(n-1) Catalogue
------------------------------
1 1 InputCatA
2 2 TilingCat
3 4 SpStandards


DIST:
-----
Distance between the spectrum and the matched GAMA object in arcsec.


IS_SBEST:
---------
In cases where multiple spectra from a given survey were matched to
the same GAMA object this flag identifies the spectrum that provides
the best redshift for that object.

SDSS:
The spectrum providing the best redshift was identified by first
considering only sciencePrimary spectra with nQ >= 3 and within 1
arcsec of the object. If there were multiple, then we selected the one
with the highest nQ value. If there were multiple with the same nQ
value, we selected the closest spectrum. In cases without any nQ >= 3
sciencePrimary spectra within 1 arcsec we simply selected first by nQ,
then by distance.

All other surveys:
The spectrum providing the best redshift was selected first by nQ, and
then (in cases of multiple spectra with the same nQ) by distance
between the object and the spectrum.

-----------------------------------------------------------------------

This DMU also provides the table ExternalzAll which contains a
relatively small number of redshifts from various literature sources,
where the original spectra from which these redshifts were measured
are not available to GAMA.

Redshifts have been collected from the following sources:

Survey # of redshifts Source
---------------------------------------------------------------------
NED 3 NED website
Updated Zwicky Catalog 214 VizieR: J/PASP/111/438
---------------------------------------------------------------------
Total 217

All redshifts were matched to GAMA objects in the same way as the
spectra above.


SPECID:
-------
NED: "NED_"common_name
UZC: "UZC"serial_number


nQ and PROB:
------------
NED: nQ = 3
PROB = 0.0
UZC: nQ = 3 if UZC_class = 0 or 1, else nQ = 2
PROB = 0.0

Address this table as gama_dr2.ExternalSpec
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - ID of matched GAMA object meta.id.cross;src
DEC deg DEC of spectrum (J2000) pos.eq.dec
DIST arcsec Distance between spectrum and matched GAMA object pos.angDistance
FILENAME - Full path and filename of the spectrum meta.id;meta.file;meta.fits
GAMA_NAME - Name of matched GAMA object meta.id.cross;src
IC_FLAG - Catalogue source(s) of matched GAMA object meta.code.member
IS_SBEST - Is this the spectrum with the best redshift of this GAMA object within the originating survey? meta.code
NQ - Normalised redshift quality (use nQ > 2 for science) meta.code.qual;src.redshift
PROB - Probability that redshift is correct stat.probability;src.redshift
RA deg RA of spectrum (J2000) pos.eq.ra
SPECID - Unique ID of spectrum meta.id;meta.main
SURVEY - Survey this spectrum originated from meta.dataset
URL - URL of the spectrum meta.ref.url;meta.file;meta.fits
URL_IMG - URL of the spectrum`s image meta.ref.url;meta.file
WMAX A Maximum wavelength of spectrum em.wl;stat.max
WMIN A Minimum wavelength of spectrum em.wl;stat.min
Z - Heliocentric redshift src.redshift
ExternalSpecAll
name: ExternalSpecAll | type: table | 2011-03-03 | Joe Liske [javascript protected email address] | version v01 |
This table lists all spectra of GAMA DR2 objects that are available from previous spectroscopic surveys (such as the SDSS), including duplicate observations. Every spectrum listed in this table is available in the GAMA DR2 database.
Address this table as gama_dr2.ExternalSpecAll
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - ID of matched GAMA object meta.id.cross;src
DEC deg DEC of spectrum (J2000) pos.eq.dec
DIST arcsec Distance between spectrum and matched GAMA object pos.angDistance
FILENAME - Full path and filename of the spectrum meta.id;meta.file;meta.fits
GAMA_NAME - Name of matched GAMA object meta.id.cross;src
IC_FLAG - Catalogue source(s) of matched GAMA object meta.code.member
IS_SBEST - Is this the spectrum with the best redshift of this GAMA object within the originating survey? meta.code
NQ - Normalised redshift quality (use nQ > 2 for science) meta.code.qual;src.redshift
PROB - Probability that redshift is correct stat.probability;src.redshift
RA deg RA of spectrum (J2000) pos.eq.ra
SPECID - Unique ID of spectrum meta.id;meta.main
SURVEY - Survey this spectrum originated from meta.dataset
URL - URL of the spectrum meta.ref.url;meta.file;meta.fits
URL_IMG - URL of the spectrum`s image meta.ref.url;meta.file
WMAX A Maximum wavelength of spectrum em.wl;stat.max
WMIN A Minimum wavelength of spectrum em.wl;stat.min
Z - Heliocentric redshift src.redshift
ExternalzAll
name: ExternalzAll | type: table | 2011-03-03 | Joe Liske [javascript protected email address] | version v01 |
This table lists a few redshifts of GAMA DR2 objects taken from the literature. The spectra from which these redshifts were measured are NOT available in the GAMA DR2 database.
Address this table as gama_dr2.ExternalzAll
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - ID of matched GAMA object meta.id.cross;src
DEC deg DEC of spectrum (J2000) pos.eq.dec
DIST arcsec Distance between spectrum and matched GAMA object pos.angDistance
GAMA_NAME - Name of matched GAMA object meta.id.cross;src
IC_FLAG - Catalogue source(s) of matched GAMA object meta.code.member
NQ - Normalised redshift quality (use nQ > 2 for science) meta.code.qual;src.redshift
PROB - Probability that redshift is correct stat.probability;src.redshift
RA deg RA of spectrum (J2000) pos.eq.ra
SPECID - Unique ID of spectrum meta.id;meta.main
SURVEY - Survey this spectrum originated from meta.dataset
Z - Heliocentric redshift src.redshift
GalexPhotometry
name: GalexPhotometry | type: group | 2012-11-13 | Ellen Andrae [javascript protected email address] | version v02 |
This DMU provides GALEX NUV and FUV photometry for GAMA DR2 objects.
GalexPhotometry
2012-11-13
Ellen Andrae

This DMU provides GALEX NUV and FUV photometry for GAMA DR2 objects.

The GALEX ultraviolet data are a combination of archival data and
pointed observations from the GALEX guest investigator (GI) program
GALEX-GAMA: UV/Optical/Near-IR/Far-IR/Radio observations of ~100k
galaxies (GI5-048; PIs: R. Tuffs, C. Popescu, US-PI: M. Seibert). The
archival data have been used to extend the ultraviolet coverage of the
GAMA regions as much as possible.

The website of the GALEX-GAMA project is
www.mpi-hd.mpg.de/galex-gama/.

This DMU provides several tables:

- GalexPhot
GALEX NUV and FUV photometry in the GAMA I survey regions provided
by the GALEX SExtractor-based pipeline.

- GalexObsInfo
Basic GALEX observational info for all GAMA DR2 objects, including
detection limits for the GALEX SExtractor-based pipeline.

- GalexSimpleMatch
Result for GAMA DR2 objects of a simple nearest neighbour match
between GalexPhot and InputCatA (within 4 arcsec).

- GalexAdvancedMatch
Result for GAMA DR2 objects of an advanced match between GalexPhot
and InputCatA. The advanced matching procedure attempts to
reconstruct the true UV flux of a given GAMA object in cases where
multiple GAMA and GALEX objects are associated with each other.

- GalexCoGPhot
GALEX NUV and FUV curve-of-growth photometry at the optical
positions of all GAMA DR2 objects.

- GalexMain
This is the main catalogue of this DMU. It should cover the needs of
most users. It duplicates the most important information from the
other catalogues in this DMU, and provides estimates of the "best"
NUV and FUV fluxes for all GAMA DR2 objects that were detected by
GALEX.


Dependencies
============
This DMU used the following inputs:

External GALEX pipeline v7
InputCat InputCatA v05
SersicPhotometry SersicCat v07


GALEX data
==========
All GI and archival data overlapping the GAMA I survey regions and
available as of 30 March 2010 were compiled for this project,
resulting in 212 GALEX tiles (circular fields 1 degree wide). These
data cover between 70% and 95% of the three equatorial regions.


Unique area (Primary vs Secondary)
==================================
GALEX tiles overlap one another. This, of course, is inevitable when
trying to cover a contiguous area with circular fields of view.
Furthermore, because we include archival survey data which is observed
on a sky grid system and pointed observations (which are not on the
sky grid system) the overlap is often very hap-hazard. There are
several ways to handle this such that we include only unique
detections and allow a precise footprint computation. We use a method
that optimizes the areal coverage and weights tiles with FUV coverage
highest.

For each GAMA region the GALEX tiles are rank-sorted by FUV exposure
time and secondary rank-sorted by NUV exposure time. This ensures that
any tile with FUV coverage takes precedence over any tile with only
NUV coverage (note that the FUV detector on GALEX is non-operational
at this time).

Once sorted, the footprint of each tile is derived from the relative
response map (effective exposure time map) by comparing it to all
neighboring tiles with a higher rank-order. In this way a "primary
map" is made for each tile indicating which parts of the field of view
are to be considered "primary" and which parts are to be considered
"secondary".

In this DMU we only consider the primary areas.

Note that photometric data from the secondary areas as provided by the
GALEX SExtractor-based pipeline are available at the GALEX-GAMA
website.


Photometry
==========
None of the fluxes and magnitudes presented in this DMU have been
corrected for the effect of foreground Milky Way dust extinction.
Should these corrections be required, they can be obtained from the
table GalacticExtinction in the InputCat DMU.

All photometry is on the AB system.

The photomtery produced by the GALEX SExtractor-based pipeline is
accompanied by artifact warning flags. We have *not* excluded any
objects from any tables in this DMU based on these flags. However, we
strongly recommend to select against objects that have the DICHROIC
REFLECTION or WINDOW REFLECTION flags raised as these reflections to
could lead to seriously corrupted fluxes (see the notes of the
GalexPhot table for details).

GalexAdvancedMatch
name: GalexAdvancedMatch | type: table | 2012-11-13 | Ellen Andrae [javascript protected email address] | version v02 |
This catalogue contains the result of an advanced match between InputCatA and GalexPhot, listing only objects included in DR2. The matching procedure takes into account the possibility of multiple matches between GALEX and GAMA objects and seeks to reconstruct the original UV flux of a given GAMA object. GAMA DR2 objects without a GALEX match are not included in this catalogue.
GalexPhotometry
GalexAdvancedMatch
v02
2012-11-13
Ellen Andrae

This catalogue contains the result of an advanced matching procedure
between InputCatA (GAMA's SDSS-based input catalogue^*) and GalexPhot.
The matching procedure takes into account the possibility of multiple
matches between GALEX and GAMA objects and seeks to reconstruct the
original UV flux of a given GAMA object.

This catalogue only includes matched GAMA DR2 objects with
S/N_NUV >= 2.5 in the redistributed flux FLUXSPLIT_NUV (see below).

Unmatched GAMA DR2 objects are not included in this catalogue. Refer to
the table GalexObsInfo for detection limits and to distinguish between
GAMA objects that were not detected in the GALEX data and those that
were not covered by GALEX.


Description of advanced matching procedure
==========================================
The advanced matching procedure takes into account the possibility of
multiple matches between GALEX and GAMA objects and seeks to
reconstruct the true UV flux of a given GAMA object.

We illustrate the routine for an example GAMA object. First, optical
shape information for the object (r-band ellipticity, position angle,
and effective radius) is extracted from the catalogue SersicCat,
and used to define a target area within which GALEX counterparts will
be deemed to be associated with the GAMA object. To take into account
scatter in apparent positions from real positions in the UV and
possibly unavailable optical shape information, the minimal search
region, i.e. optical target area, is a circle of radius 4 arcsec (the
matching radius used in GalexSimpleMatch). The question that is then
to be answered is which GALEX objects in GalexPhot have their central
coordinates within this optically defined search region. The number,
the IDs and the total flux of all such GALEX objects are recorded in
columns NMATCHUV, UVIDXLIST and FLUXTOT_XXX, respectively.

Since it is possible that a GALEX object may itself be extended, or
that it has more than one potential close-lying optical counterpart in
InputCatA, we also need to take into account the possibility that one
or more of the GALEX objects in the search region around the GAMA
object may themselves be related to further GAMA objects. Hence, in
the second step of the advanced matching procedure, a UV area is
constructed for each GALEX object within the optical search region,
using the object's position angle, ellipticity and size along its
semimajor axis from GalexPhot. InputCatA is then searched for GAMA
objects within the UV area of each of the GALEX objects. The number
and IDs of the GAMA objects found in this step are recorded in the
columns NMATCHOPT and OPTIDXLIST^*. The columns NMATCHUV and UVIDXLIST
for the GAMA objects found in this step are updated to include this
GALEX object.

In cases where there is a 1-to-1 match all of the flux of the GALEX
object is attributed to the matching GAMA object. This is by far the
most common case (68%). If, however, there is more than one potential
optical counterpart to one or more of the GALEX objects in the optical
search region, the UV flux of each of the GALEX objects is split among
all potential optical counterparts of that GALEX object, weighted
inversely by angular distance (using a minimum distance of 0.3 arcsec
to account for positional errors). Finally, the UV flux contributions
from all of the GALEX objects in the optical search radius to the GAMA
object under consideration are summed up and recorded in the columns
FLUXSPLIT_XXX. FLUXSPLITERR_XXX is the square-root of the weighted
quadratic sum of the errors of all GALEX objects from which the object
under consideration received a flux contribution, where the weights in
the quadratic sum are the same weights as those used for the flux
itself.

Finally, we purge from the catalogue all GAMA objects with
FLUXSPLIT_NUV / FLUXSPLITERR_NUV < 2.5.

Note that in cases where there is a 1-to-1 match between a GAMA and a
GALEX object we have FLUXTOT_XXX = FLUXSPLIT_XXX. Furthermore, in
these cases FLUXTOT_XXX is equal to FLUX_XXX from GalexPhot of the
GALEX object identified as the GAMA object's nearest GALEX neighbour
in GalexSimpleMatch. In other words, in these "simple" cases the
advanced matching procedure returns the same result for the UV fluxes
of a given GAMA object as the simple nearest neighbour matching.

Also note that it is possible for a GAMA object not to have a
FLUXTOT_XXX value associated with it but to still have a FLUXSPLIT_XXX
value associated with it. This will happen if there are no GALEX
objects within the GAMA object's optical search region (leading to
FLUXTOT_XXX being set to its default value of -99.0) and if the GAMA
object lies inside the UV search region(s) of one or more GALEX
objects, which in turn lie in the optical search region of at least
one other GAMA object. In this case the first GAMA object participates
in the re-distribution of the UV flux from these GALEX objects,
leading to FLUXSPLIT_XXX values != -99.0.

We also point out that there are substantial differences between the
objects included in this catalogue and those included in
GalexSimpleMatch. An object may be included in this catalogue but not
in GalexSimpleMatch and vice versa. The former happens when a GAMA
object is more than 4 arcsec away from its nearest GALEX neighbour but
still receives flux from one or more GALEX objects during the flux
re-distribution (with S/N_NUV >= 2.5). The latter happens when the
flux redistribution results in the S/N of the NUV flux received by a
GAMA object listed in GalexSimpleMatch dropping below the threshold of
2.5.

We recognise that the above flux redistribution scheme may not be
optimal, and that users may wish to apply other recipes for
distributing the UV flux among the optical counterparts (e.g. using
additional prior astrophysical information). This is easily achieved
given that we identify all GALEX and GAMA objects involved in a given
match in the columns UVIDXLIST and OPTIDXLIST^*.

We caution that the UV flux estimates reported in columns
FLUXSPLIT_XXX are only correct in a statistical sense, i.e. when
considering a large population of objects. However, for individual
objects they are necessarily imprecise.

The default value for non-measurements is -99.0.


^* Additional note
==================
This catalogue is actually slightly inconsistent with the rest of the
GAMA DR2 because the advanced matching procedure described above was
carried out using v06 of InputCatA, whereas the version released in
DR2 is v05. InputCatAv05 is the GAMA I master input catalogue, whereas
InputCatAv06 is the version used for GAMA II. v06 was chosen for the
advanced matching between GalexPhot and InputCatA because it has a
slightly fainter flux limit than v05 (r < 20.0 in v06 vs. r < 19.8 in
v05), and because it includes point sources (which were excluded from
v05). Both of these differences should make the matching and flux
re-distribution more reliable.

As explained above, column OPTIDXLIST lists all GAMA objects (using
the SDSS identifier OBJID) that are involved in the matching. However,
since InputCatAv06 contains significantly more objects than v05, a
number of the objects listed in column OPTIDXLIST are not found in
InputCatAv05 as released in GAMA DR2. To be precise, of the 62,036
unique objects listed in column OPTIDXLIST 9686 are not in
InputCatAv05.

Furthermore, we note that InputCatAv05 is based on SDSS DR6, whereas
InputCatAv06 is based on SDSS DR7. The SDSS OBJID used in column
OPTIDXLIST is hence the SDSS DR7 OBJID. However, since a small
fraction of objects changed their SDSS OBJID between DR6 and DR7,
there are 546 objects that are listed in column OPTIDXLIST with a
different OBJID than that used in InputCatAv05.

Address this table as gama_dr2.GalexAdvancedMatch
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - Unique ID of GAMA object meta.id
FLUXSPLITERR_FUV microJy Redistributed FUV flux error phot.flux;em.UV.100-200nm;stat.error
FLUXSPLITERR_NUV microJy Redistributed NUV flux error phot.flux;em.UV.200-300nm;stat.error
FLUXSPLIT_FUV microJy Redistributed FUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.100-200nm
FLUXSPLIT_NUV microJy Redistributed NUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.200-300nm
FLUXTOTERR_FUV microJy Total FUV flux error phot.flux;em.UV.100-200nm;stat.error
FLUXTOTERR_NUV microJy Total NUV flux error phot.flux;em.UV.200-300nm;stat.error
FLUXTOT_FUV microJy Total FUV flux of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.flux;em.UV.100-200nm
FLUXTOT_NUV microJy Total NUV flux of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.flux;em.UV.200-300nm
FUVFLAG - Combination of the FUV artifact flags of all GALEX objects involved in the matching meta.code;em.UV.100-200nm
MAGSPLITERR_FUV mag Redistributed FUV AB magnitude error phot.mag;em.UV.100-200nm;stat.error
MAGSPLITERR_NUV mag Redistributed NUV AB magnitude error phot.mag;em.UV.200-300nm;stat.error
MAGSPLIT_FUV mag Redistributed FUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.100-200nm
MAGSPLIT_NUV mag Redistributed NUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.200-300nm
MAGTOTERR_FUV mag Total FUV AB magnitude error phot.mag;em.UV.100-200nm;stat.error
MAGTOTERR_NUV mag Total NUV AB magnitude error phot.mag;em.UV.200-300nm;stat.error
MAGTOT_FUV mag Total FUV AB magnitude of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.mag;em.UV.100-200nm
MAGTOT_NUV mag Total NUV AB magnitude of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.mag;em.UV.200-300nm
NMATCHOPT - Number of GAMA objects involved in the matching meta.number
NMATCHUV - Number of GALEX objects involved in the matching meta.number
NUVFLAG - Combination of the NUV artifact flags of all GALEX objects involved in the matching meta.code;em.UV.200-300nm
OBJID - SDSS objid meta.id
OPTIDXLIST - ID list of GAMA objects used in the flux redistribution calculation using SDSS OBJID; string always ends with a comma -
UVIDXLIST - ID list of GALEX object used in the flux redistribution calculation using NAME from GalexPhot; string always ends with a comma -
GalexCoGPhot
name: GalexCoGPhot | type: table | 2012-11-13 | Ellen Andrae [javascript protected email address] | version v02 |
This catalogue provides GALEX NUV and FUV curve-of-growth photometry for all GAMA DR2 objects.
GalexPhotometry
GalexCoGPhot
v02
2012-11-13
Ellen Andrae

In addition to the GALEX-pipeline-generated photometry of "blind"
GALEX NUV detections presented in GalexPhot, we provide in this
catalogue NUV and FUV photometric measurements at the a priori known
optical positions of GAMA DR2 objects using a curve-of-growth (CoG)
method.

Our CoG method (described in detail below) requires not only the
positions but also the ellipticities and position angles of the
galaxies to be photometered. We take this information from the most
reliable source of shape information for GAMA galaxies, SersicCatAll
in the SersicPhotometry DMU.


Description of CoG method
=========================
For each object to be analysed, the local background level and its
(Poissonian) error, sigma_bkg, is estimated in the NUV/FUV data at the
object's optical position, and the background is subtracted. An
elliptical aperture is constructed from the object's r-band position,
effective radius (GAL_RE_R), ellipticity (GAL_ELLIP_R) and position
angle (GAL_PA_R) from SersicCatAll. This aperture is then convolved
with the GALEX PSF, assumed to be a Gaussian with a FWHM of 5.3 arcsec.

The flux is then averaged in elliptical annuli of the above shape of
width 3 arcsec (as measured along the object's major axis). The
"integration radius" (along the major axis) of the target is then
defined as the smaller of the following: the outer radius of the
smallest annulus in which the average flux falls below the background
level plus 1.0 sigma_bkg or the outer radius + 3 arcsec of the
smallest annulus in which the average flux falls below the background
level plus 1.5 sigma_bkg. This was found to be a good compromise
between including very faint target emission at large radii on the one
hand and the need to avoid pure noise integration or blending with
neighbouring objects on the other. This integration radius is listed
in columns RE_CRIT_XXX in the catalogue.

Objects for which the flux in the innermost annulus (0-3 arcsec) is
already below the level of the background plus 1.5 sigma_bkg have
RE_CRIT_XXX set to 0. Furthermore, objects with RE_CRIT_XXX = 3 arcsec
must also be considered non-detections since they are smaller than the
GALEX PSF.

The flux of the target is then determined by integrating the flux
inside the elliptical aperture of size RE_CRIT_XXX. If this flux is
negative (i.e. a complete non-detection) then all flux columns are set
to 99. Note that apart from this "cut", all flux measurements are
reported in this catalogue, i.e. no S/N limit is applied.

In order to avoid contamination from neighbouring sources (taken from
InputCatA), a circular area with a radius (not diameter) of 5.3 arcsec
is masked around these. Any masked pixels inside a galaxy's
integration aperture are accounted for by renormalizing the unmasked
galaxy flux measured in the same elliptical annuli as the masked
pixels. Galaxies where this was necessary are flagged in the columns
CONFSOURCE_XXX. Objects for which the flux profile never reaches the
level of the background plus 1.5 sigma_bkg due to the flux of
neighbouring objects outside of their masks have their fluxes set to
999. Objects with a masked area in the central radius bin are deemed
to be unmeasurable and their flux values are set to -99.

Objects with RE_CRIT_NUV > RE_CRIT_FUV + 30 arcsec are very likely to
have a NUV measurement that was contaminated by a neighboring
source. (Especially stars tend to be much fainter in the FUV, thus
even very bright stars are very unlikely to have excess FUV flux
outside the masked area, even though they may have excess NUV flux
outside the masked area.) Therefore, all NUV columns are set to 999 in
these cases.

Objects not covered by the GALEX data (or those where the coverage of
the surroundings was not sufficient for a background estimate) also
have their fluxes set to -99.

Address this table as gama_dr2.GalexCoGPhot
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - Unique ID of GAMA object meta.id
CONFSOURCE_FUV - FUV flag indicating whether masking occurred meta.code
CONFSOURCE_NUV - NUV flag indicating whether masking occurred meta.code
CPSERR_FUV counts/s FUV counts per second error phot.count;em.UV.100-200nm;stat.error
CPSERR_NUV counts/s NUV counts per second error phot.count;em.UV.200-300nm;stat.error
CPS_FUV counts/s FUV counts per second phot.count;em.UV.100-200nm
CPS_NUV counts/s NUV counts per second phot.count;em.UV.200-300nm
FLUXERR_FUV microJy FUV flux error phot.flux;em.UV.100-200nm;stat.error
FLUXERR_NUV microJy NUV flux error phot.flux;em.UV.200-300nm;stat.error
FLUX_FUV microJy FUV flux phot.flux;em.UV.100-200nm
FLUX_NUV microJy NUV flux phot.flux;em.UV.200-300nm
HP_RAD_FUV arcsec FUV radius enclosing 50% of the total flux phys.size.radius;em.UV.100-200nm
HP_RAD_NUV arcsec NUV radius enclosing 50% of the total flux phys.size.radius;em.UV.200-300nm
MAGERR_FUV mag FUV magnitude error phot.mag;em.UV.100-200nm;stat.error
MAGERR_NUV mag NUV magnitude error phot.mag;em.UV.200-300nm;stat.error
MAG_FUV mag FUV magnitude phot.mag;em.UV.100-200nm
MAG_NUV mag NUV magnitude phot.mag;em.UV.200-300nm
OBJID - SDSS objid meta.id
RE_CRIT_FUV arcsec FUV integration radius (multiple of 3 arcsec) phys.size.radius;em.UV.100-200nm
RE_CRIT_NUV arcsec NUV integration radius (multiple of 3 arcsec) phys.size.radius;em.UV.200-300nm
GalexMain
name: GalexMain | type: table | 2012-11-13 | Ellen Andrae [javascript protected email address] | version v02 |
This is the main catalogue of the GalexPhotometry DMU. It reproduces the most important information from the other catalogues in this DMU and provides a best estimate of the NUV and FUV fluxes of all GAMA DR2 objects that were detected by GALEX.
GalexPhotometry
GalexMain
v02
2012-11-13
Ellen Andrae

This is the main catalogue of the GalexPhotometry DMU. It reproduces
the most important information from the other catalogues in this DMU
and provides a best estimate of the NUV and FUV fluxes of all GAMA DR2
objects that were detected by GALEX.

Included in this catalogue are all GAMA DR2 objects that either

- have an entry in GalexSimpleMatch
or
- have an entry in GalexAdvancedMatch
or
- have an entry in GalexCoGPhot with S/N_NUV >= 2.5 and integration
radius RE_CRIT_NUV >= 6 arcsec

The S/N criterion applied to GalexCoGPhot is the same as that used for
GalexPhot and GalexAdvancedMatch. Note that GAMA DR2 objects that were
not detected by GALEX (in the sense that they do not match any of the
criteria above) are not included in this catalogue. Refer to the table
GalexObsInfo for nominal detection limits and to distinguish between
GAMA objects that were not detected in the GALEX data and those that
were not covered by GALEX. For DR2 objects not included in the present
catalogue you can also turn to the table GalexCoGPhot to find out if
they were "detected" at S/N_NUV < 2.5, i.e. essentially to find upper
flux limits for these objects.

This catalogue provides the following information:

- In columns 50-75 (NN_GGOID - NN_POSANGERR_NUV) we reproduce the main
information on the GAMA object's nearest neighbour GALEX object from
GalexPhot (catalogue of UV detections and photometry from the GALEX
SExtractor-based pipeline), using GalexSimpleMatch to connect the
two. The columns NN_FLUX_XXX contain the fluxes of the nearest
neighbour GALEX object as measured by the GALEX SExtractor-based
pipeline. For more information refer to the notes of the
GalexSimpleMatch and GalexPhot tables.

- In columns 16-35 (NMATCHUV - SPLIT_MAGERR_FUV) we reproduce the main
information from GalexAdvancedMatch. This table contains the result
(for GAMA DR2 objects) of an advanced match between GalexPhot and
InputCatA. The advanced matching procedure attempts to reconstruct
the true UV flux of a given GAMA object in cases where multiple GAMA
and GALEX objects are associated with each other. This reconstructed
flux is reported in columns SPLIT_FLUX_XXX. The columns TOT_FLUX_XXX
contain the total flux of all GALEX objects associated with a given
GAMA object. For more information refer to the notes of the
GalexAdvancedMatch table.

- In columns 36-49 (COG_FLUX_NUV - COG_CONFSOURCE_FUV) we reproduce
the main information from GalexCoGPhot. This table contains
photometric measurements (using a curve-of-growth method) at the a
priori known optical positions of GAMA objects. The columns
COG_FLUX_XXX contain the fluxes returned by the CoG method. For more
information refer to the notes of the GalexCoGPhot table.

- In columns 7-15 (BEST_FLUX_NUV - BEST_METHOD) we report our best
estimate of the NUV and FUV fluxes of a given GAMA object. In these
columns we make appropriate choices among the various fluxes
available for a given object (from the advanced matching or CoG
methods), and we strongly recommend the use of these BEST fluxes.

In cases where there is an unambiguous 1-to-1 correspondence between
a GAMA and a GALEX object we believe the fluxes returned by the
GALEX pipeline for the GALEX object to be the most appropriate. Note
that in these cases the nearest neighbour and advanced matching
procedures of course return the same results for the UV fluxes of a
given GAMA object, i.e. NN_FLUX_XXX = TOT_FLUX_XXX = SPLIT_FLUX_XXX.

In cases where the GAMA object is very extended or where there are
multiple GAMA and/or GALEX objects associated with each other we
believe our CoG photometry to be superior.

However, in cases where the CoG measurements have failed (for
whatever reason, see the notes of the GalexCoGPhot table) we resort
to the reconstructed fluxes SPLIT_FLUX_XXX returned by the advanced
matching procedure.

We therefore set BEST_FLUX_XXX according to the following rules:

- If only one of COG_FLUX_NUV and SPLIT_FLUX_NUV is available in
this catalogue then the BEST columns are set to the corresponding
columns of the available flux method.

- If both COG_FLUX_NUV and SPLIT_FLUX_NUV are available in this
catalogue then the BEST columns are set to the corresponding
columns of the CoG method if NMATCHUV > 1 or NMATCHOPT > 1 or
GAL_RE_R > 10 arcsec, where GAL_RE_R is the r-band effective
radius from SersicCatAll. Otherwise the BEST columns are set to
the corresponding SPLIT columns.

The flux method used for the BEST columns is recorded in column
BEST_METHOD (CoG or AdvancedMatch).

Note that for a COG_FLUX_NUV value to be present *in this catalogue*
it must have S/N >= 2.5 (see above).

Also note that there are 250 objects in this catalogue with neither
AdvancedMatch nor CoG entries. These objects were included here only
because they have an entry in GalexSimpleMatch, meaning they have at
least one S/N_NUV >= 2.5 GALEX object from GalexPhot within 4 arcsec.
However, all of these have multiple GALEX objects associated with
them. Hence one should not be tempted to use the UV flux of the
nearest GALEX neighbour as the BEST flux in these cases.


The default value for missing entries in this table is -999.

Address this table as gama_dr2.GalexMain
Name Unit Description UCD (hover for description)
Name Unit Description UCD
BEST_FLUXERR_FUV microJy Best estimate FUV flux error phot.flux;em.UV.100-200nm;stat.error
BEST_FLUXERR_NUV microJy Best estimate NUV flux error phot.flux;em.UV.200-300nm;stat.error
BEST_FLUX_FUV microJy Best estimate of the GAMA object`s FUV flux phot.flux;em.UV.100-200nm
BEST_FLUX_NUV microJy Best estimate of the GAMA object`s NUV flux phot.flux;em.UV.200-300nm
BEST_MAGERR_FUV mag Best estimate FUV magnitude error phot.mag;em.UV.100-200nm;stat.error
BEST_MAGERR_NUV mag Best estimate NUV magnitude error phot.mag;em.UV.200-300nm;stat.error
BEST_MAG_FUV mag Best estimate of the GAMA object`s FUV magnitude phot.mag;em.UV.100-200nm
BEST_MAG_NUV mag Best estimate of the GAMA object`s NUV magnitude phot.mag;em.UV.200-300nm
BEST_METHOD - Method used for the best flux estimates (AdvancedMatch or CoG) meta.code
CATAID - Unique ID of GAMA object meta.id
COG_CONFSOURCE_FUV - CoG FUV flag indicating whether masking occurred meta.code
COG_CONFSOURCE_NUV - CoG NUV flag indicating whether masking occurred meta.code
COG_FLUXERR_FUV microJy CoG FUV flux error phot.flux;em.UV.100-200nm;stat.error
COG_FLUXERR_NUV microJy CoG NUV flux error phot.flux;em.UV.200-300nm;stat.error
COG_FLUX_FUV microJy CoG FUV flux at the position of the GAMA object phot.flux;em.UV.100-200nm
COG_FLUX_NUV microJy CoG NUV flux at the position of the GAMA object phot.flux;em.UV.200-300nm
COG_HP_RAD_FUV arcsec CoG FUV radius enclosing 50% of the total flux phys.size.radius;em.UV.100-200nm
COG_HP_RAD_NUV arcsec CoG NUV radius enclosing 50% of the total flux phys.size.radius;em.UV.200-300nm
COG_MAGERR_FUV mag CoG FUV magnitude error phot.mag;em.UV.100-200nm;stat.error
COG_MAGERR_NUV mag CoG NUV magnitude error phot.mag;em.UV.200-300nm;stat.error
COG_MAG_FUV mag CoG FUV magnitude phot.mag;em.UV.100-200nm
COG_MAG_NUV mag CoG NUV magnitude phot.mag;em.UV.200-300nm
COG_RE_CRIT_FUV arcsec CoG FUV integration radius (multiple of 3 arcsec) phys.size.radius;em.UV.100-200nm
COG_RE_CRIT_NUV arcsec CoG NUV integration radius (multiple of 3 arcsec) phys.size.radius;em.UV.200-300nm
DEC deg Declination of GAMA object (J2000) pos.eq.dec
EFF_EXPTIME_FUV s FUV effective exposure time (relative response) obs.exposure;em.UV.100-200nm
EFF_EXPTIME_NUV s NUV effective exposure time (relative response) obs.exposure;em.UV.200-300nm
FUVFLAG - Combination of the FUV artifact flags of all GALEX objects involved in advanced matching procedure meta.code;em.UV.100-200nm
NMATCHOPT - Number of GAMA objects involved in advanced matching procedure meta.number
NMATCHUV - Number of GALEX objects involved in advanced matching procedure meta.number
NN_ARTIFACT_FUV - FUV artifact flag of nearest neighbour GALEX object (see GalexPhot notes) meta.code;em.UV.100-200nm
NN_ARTIFACT_NUV - NUV artifact flag of nearest neighbour GALEX object (see GalexPhot notes) meta.code;em.UV.200-300nm
NN_DEC_GALEX deg Declination of nearest neighbour GALEX object (J2000) pos.eq.dec
NN_DIST arcsec Distance between GAMA object and nearest neighbour GALEX object pos.angDistance
NN_FLUX50_RADIUS_FUV arcsec FUV 50 percent fraction-of-light radius of nearest neighbour GALEX object phys.size.radius;em.UV.100-200nm
NN_FLUX50_RADIUS_NUV arcsec NUV 50 percent fraction-of-light radius of nearest neighbour GALEX object phys.size.radius;em.UV.200-300nm
NN_FLUXERR_FUV microJy FUV flux error of nearest neighbour GALEX object using NUV aperture phot.flux;em.UV.100-200nm;stat.error
NN_FLUXERR_NUV microJy NUV flux error of nearest neighbour GALEX object phot.flux;em.UV.200-300nm;stat.error
NN_FLUX_FUV microJy FUV flux of nearest neighbour GALEX object using NUV aperture phot.flux;em.UV.100-200nm
NN_FLUX_NUV microJy NUV flux of nearest neighbour GALEX object phot.flux;em.UV.200-300nm
NN_GGOID - Global Object ID of nearest neighbour GALEX object meta.id
NN_MAGERR_FUV mag FUV AB Kron magnitude error of nearest neighbour GALEX object using NUV aperture phot.mag;em.UV.100-200nm;stat.error
NN_MAGERR_NUV mag NUV AB Kron magnitude error of nearest neighbour GALEX object phot.mag;em.UV.200-300nm;stat.error
NN_MAG_FUV mag FUV AB Kron magnitude of nearest neighbour GALEX object using NUV aperture phot.mag;em.UV.100-200nm
NN_MAG_NUV mag NUV AB Kron magnitude of nearest neighbour GALEX object phot.mag;em.UV.200-300nm
NN_MANY2ONE - Number of GAMA objects the nearest neighbour GALEX object is matched to meta.number
NN_NMATCH4 - Number of GALEX objects found within 4 arcsec of GAMA object meta.number
NN_POSANGERR_NUV deg NUV position angle error of nearest neighbour GALEX object pos.posAng;stat.error
NN_POSANG_NUV deg NUV position angle (east of north) of nearest neighbour GALEX object pos.posAng
NN_RA_GALEX deg Right Ascension of nearest neighbour GALEX object (J2000) pos.eq.ra
NN_SEMIMAJORERR_NUV arcsec NUV semimajor axis error of nearest neighbour GALEX object phys.size.radius;stat.error
NN_SEMIMAJOR_NUV arcsec NUV semimajor axis of nearest neighbour GALEX object phys.size.radius;em.UV.200-300nm
NN_SEMIMINORERR_NUV arcsec NUV semiminor axis error of nearest neighbour GALEX object phys.size.radius;stat.error
NN_SEMIMINOR_NUV arcsec NUV semiminor axis of nearest neighbour GALEX object phys.size.radius;em.UV.200-300nm
NN_SFLAGS_FUV - FUV Sextraxtor extraction flags of nearest neighbour GALEX object meta.code;em.UV.100-200nm
NN_SFLAGS_NUV - NUV Sextraxtor extraction flags of nearest neighbour GALEX object meta.code;em.UV.200-300nm
NUVFLAG - Combination of the NUV artifact flags of all GALEX objects involved in advanced matching procedure meta.code;em.UV.200-300nm
OBJID - SDSS objid meta.id
RA deg Right Ascension of GAMA object (J2000) pos.eq.ra
SPLIT_FLUXERR_FUV microJy Error on redistributed FUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.100-200nm;stat.error
SPLIT_FLUXERR_NUV microJy Error on redistributed NUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.200-300nm;stat.error
SPLIT_FLUX_FUV microJy Redistributed FUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.100-200nm
SPLIT_FLUX_NUV microJy Redistributed NUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.200-300nm
SPLIT_MAGERR_FUV mag Error on redistributed FUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.100-200nm;stat.error
SPLIT_MAGERR_NUV mag Error on redistributed NUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.200-300nm;stat.error
SPLIT_MAG_FUV mag Redistributed FUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.100-200nm
SPLIT_MAG_NUV mag Redistributed NUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.200-300nm
TOT_FLUXERR_FUV microJy Error on total FUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.100-200nm;stat.error
TOT_FLUXERR_NUV microJy Error on the total NUV flux of all GALEX objects associated with GAMA object phot.flux;em.UV.200-300nm;stat.error
TOT_FLUX_FUV microJy Total FUV flux of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.flux;em.UV.100-200nm
TOT_FLUX_NUV microJy Total NUV flux of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.flux;em.UV.200-300nm
TOT_MAGERR_FUV mag Error on total FUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.100-200nm;stat.error
TOT_MAGERR_NUV mag Error on total NUV AB magnitude of all GALEX objects associated with GAMA object phot.mag;em.UV.200-300nm;stat.error
TOT_MAG_FUV mag Total FUV AB magnitude of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.mag;em.UV.100-200nm
TOT_MAG_NUV mag Total NUV AB magnitude of all GALEX objects associated with GAMA object (unweighted sum of the flux) phot.mag;em.UV.200-300nm
GalexObsInfo
name: GalexObsInfo | type: table | 2012-11-13 | Ellen Andrae [javascript protected email address] | version v02 |
This catalogue provides basic GALEX observational information, i.e. exposure times, background levels and detection limits, for all GAMA DR2 objects.
GalexPhotometry
GalexObsInfo
v02
2012-11-13
Ellen Andrae

This catalogue provides basic GALEX observational information,
i.e. exposure times, background levels and GALEX Sextractor-based
pipeline detection limits, for (almost) all DR2 objects. (Eleven DR2
objects had to be excluded for technical reasons.)

This catalogue includes all objects that are currently not covered by
GALEX NUV data. The rows for these objects are "empty" (containing
-99). As the matched catalogues GalexSimpleMatch and
GalexAdvancedMatch only contain matched objects, we report these
"empty" rows here to enable the user to discriminate between objects
that were covered by GALEX (in the NUV) but not detected, and those
that were not covered by GALEX.


Detection limits
================
The columns NUVFLUXLIMITXX and FUVFLUXLIMITXX give the GALEX
Sextractor-based pipeline detection limits at this position for a
circular source for the given signal-to-noise cut. They use a default
radius of 3.4" or, if it is listed and greater than 3.4", the radius
given by GAL_RE_R in SersicCatv07. (Note that SersicCatv07 only covers
the nominal GAMA I survey regions, which are sub-regions of the
nominal GAMA II survey regions, which are in turn sub-regions of the
regions covered by InputCatAv06.)

Users can calculate detection limits in units of counts per second for
any desired signal-to-noise ration (SN) themselves using the formula:

fluxlimitcps = ((SN)^2 + sqrt((SN)^4 + 4*eff_exptime*limcat*area*(SN)^2)) / (2*eff_exptime)

where NUV or FUV quantities should be used accordingly. "limcat"
denotes the background brightness in counts per second, defined as
follows in terms of the columns BKGRND_FLUX_NUV and BKGRND_FLUX_FUV:

limcat = BKGRND_FLUX / CUJ

where CUJ_NUV = 33.7286987304688 and CUJ_FUV = 107.647003173828.

To obtain fluxlimits in microJy, use

fluxlimit = fluxlimitcps * CUJ

Address this table as gama_dr2.GalexObsInfo
Name Unit Description UCD (hover for description)
Name Unit Description UCD
BKGRND_FLUX_FUV microJy/arcsec^2 FUV sky background surface brightness phot.flux;em.UV.100-200nm;src.net
BKGRND_FLUX_NUV microJy/arcsec^2 NUV sky background surface brightness phot.flux;em.UV.200-300nm;src.net
CATAID - Unique ID of GAMA object meta.id
EFF_EXPTIME_FUV s FUV effective exposure time (relative response) obs.exposure;em.UV.100-200nm
EFF_EXPTIME_NUV s NUV effective exposure time (relative response) obs.exposure;em.UV.200-300nm
FUVFLUXLIMIT10 microJy S/N=10 FUV flux detection limit for a circular source at this position phot.flux;em.UV.100-200nm;stat.min
FUVFLUXLIMIT2p5 microJy S/N=2.5 FUV flux detection limit for a circular source at this position phot.flux;em.UV.100-200nm;stat.min
FUVFLUXLIMIT5 microJy S/N=5 FUV flux detection limit for a circular source at this position phot.flux;em.UV.100-200nm;stat.min
FUVMAGLIMIT10 mag S/N=10 FUV flux detection limit for a circular source at this position phot.mag;em.UV.100-200nm;stat.min
FUVMAGLIMIT2p5 mag S/N=2.5 FUV flux detection limit for a circular source at this position phot.mag;em.UV.100-200nm;stat.min
FUVMAGLIMIT5 mag S/N=5 FUV flux detection limit for a circular source at this position phot.mag;em.UV.100-200nm;stat.min
NUVFLUXLIMIT10 microJy S/N=10 NUV flux detection limit for a circular source at this position phot.flux;em.UV.200-300nm;stat.min
NUVFLUXLIMIT2p5 microJy S/N=2.5 NUV flux detection limit for a circular source at this position phot.flux;em.UV.200-300nm;stat.min
NUVFLUXLIMIT5 microJy S/N=5 NUV flux detection limit for a circular source at this position phot.flux;em.UV.200-300nm;stat.min
NUVMAGLIMIT10 mag S/N=10 NUV flux detection limit for a circular source at this position phot.mag;em.UV.200-300nm;stat.min
NUVMAGLIMIT2p5 mag S/N=2.5 NUV flux detection limit for a circular source at this position phot.mag;em.UV.200-300nm;stat.min
NUVMAGLIMIT5 mag S/N=5 NUV flux detection limit for a circular source at this position phot.mag;em.UV.200-300nm;stat.min
OBJID - SDSS objid meta.id
GalexPhot
name: GalexPhot | type: table | 2012-11-13 | Mark Seibert [javascript protected email address] | version v02 |
This catalogue provides GALEX NUV and FUV photometry for primary sources with S/N_NUV >= 2.5 in the GAMA I survey regions. This photometry was derived using the GALEX SExtractor-based pipeline.
GalexPhotometry
GalexPhot
v02
2012-11-13
Mark Seibert

This catalogue provides GALEX NUV and FUV photometry for primary
sources with S/N_NUV >= 2.5 in the GAMA I survey regions. The present
catalogue was created at Caltech using a new version of the GALEX
SExtractor-based pipeline (v7).


Some points to note
===================
Matched apertures: This catalogue is NUV-centric. The S/N of the
NUV data is significantly higher than that of the FUV data. We have
taken advantage of this by performing source detection only in the
NUV, and then carrying out photometry in both bands in apertures
defined in the NUV. This has the advantage of improving the
reliability and completeness of the FUV detections and providing
meaningful UV colors. Please note however that, because source
detection is carried out in the NUV, it is possible to obtain negative
flux measurements in the FUV. Note also that all catalogue columns
without an explicit band reference are derived from the NUV.

Calibration: The major changes to the GALEX calibration compared to
previous versions include updates to the flat fields, flux response
trend with time, and a magnitude zero-point correction (0.043 mag
fainter in NUV and 0.033 mag fainter in FUV). Further information can
be found on the GALEX web page or detailed in this document. Note that
due to the time trend and flat field changes one cannot simply apply
fixed zero-point corrections to the previus versions of this
catalogue.

Deblending/Shredding: The deblending threshold parameter has been
modified to improve the shredding of extended sources. Prior to v7 the
pipeline was tuned for point sources. With v7 a better compromise has
been reached that reduces the shredding for extended objects less than
1 arcmin in diameter.

Astrometry: The GALEX PSF is ~5 arcsec and the astrometry is only
accurate to within ~0.3 arcsec. Analysing the offsets between GALEX
and GAMA optical positions we find that the offsets are not systematic
and vary from GALEX tile to tile. The principle cause of the
astrometric offsets is the limited precision of astrometric catalogues
used to derive the plate solutions within the GALEX pipeline.

Finally we note that the present version of this catalogue was created
using the methods and techniques of the GALEX CATalog Team
(GCATT). This is a large project underway to produce a definitive
GALEX source catalogue.


Artifact flags
==============
This catalogue contains artifact warning flags for both the NUV and the
FUV. These are bitwise-encoded unsigned integers, each of which is the
bitwise logical 'or' of some or none of the possible flags listed
below. The flags are applied to regions of the image derived entirely
from geometry based on knowledge of the detector's orientation and
(for some flags) an a priori estimate of the NUV/FUV brightness of
known stars. Source brightness criteria for flagging are generous,
meaning that false-positives, especially for 'edge' flags, are common.
False-negatives are much rarer, but definitely occur with some
regularity.

In practice, the DICHROIC REFLECTION and WINDOW REFLECTION flags are
the only flags that one should always select against as these could
lead to seriously corrupt fluxes.


Flag name | Bit | Flag value | Meaning
| (LSB=1) | (base 10) |
----------|---------|--------------------------------------------------------
Edge | 1 | 1 | Detector bevel edge reflection (NUV only)
----------|---------|--------------------------------------------------------
Window | 2 | 2 | Detector window reflection (NUV only)
----------|---------|--------------------------------------------------------
Dichroic | 3 | 4 | Dichroic reflection
----------|---------|--------------------------------------------------------
Varpix | 4 | 8 | Varible pixel based on time slices.
----------|---------|--------------------------------------------------------
Brtedge | 5 | 16 | Bright star near edge of field (NUV only).
| | | Just like #1 but with a higher count rate
| | | requirement (about 10 cps) on the
| | | generating star. Cuts down on false
| | | positives at the cost of a higher false
| | | negative rate.
----------|---------|--------------------------------------------------------
Rim | 6 | 32 | Detector rim (annulus) proximity
| | | (>0.6 deg > from FOV center).
----------|---------|--------------------------------------------------------
Dimask | 7 | 64 | Dichroic reflection artifact mask flag.
| | | Used only when a coadd has enough visits
| | | at enough position angles that masking
| | | the dichroic reflection doesn't decrease
| | | flux by more than 1/3.
----------|---------|--------------------------------------------------------
Varmask | 8 | 128 | Masked pixel determined by varpix.
----------|---------|--------------------------------------------------------
Hotmask | 9 | 256 | Masked detector hotspots.


As an example, if pixel N for an image is overlayed by an edge
reflection region and is in the rim region (i.e. near the detector
edge), its value is:

Flag(N) = 2^(1 - 1) = 1 (edge condition)

or 2^(6 - 1) = 32 (rim condition)

1 + 32 = 33 (bit coded value for both conditions)


Default values
==============
The default value for blank entries is -99 (used e.g. for FUV
quantities when FUV data are missing). The value 99 is assigned to
magnitudes when the corresponding flux is negative (see above).


Known issues
============
This catalogue contains a few GALEX objects which are closer to their
nearest GALEX neighbor than the FWHM of the GALEX PSF. These duplicate
detections are an artifact of the mosaicing of the primary areas: in
these cases an object is detected separately on two different tiles
with slightly different coordinates, and with each detection lying in
the primary area of its tile.

Address this table as gama_dr2.GalexPhot
Name Unit Description UCD (hover for description)
Name Unit Description UCD
ARTIFACT_FUV - FUV artifact flag (see notes) meta.code;em.UV.100-200nm
ARTIFACT_NUV - NUV artifact flag (see notes) meta.code;em.UV.200-300nm
BKGRND_FLUX_FUV microJy/arcsec^2 FUV sky background surface brightness phot.flux;em.UV.100-200nm;src.net
BKGRND_FLUX_NUV microJy/arcsec^2 NUV sky background surface brightness phot.flux;em.UV.200-300nm;src.net
BKGRND_MAG_FUV mag/arcsec^2 FUV sky background surface brightness phot.mag;em.UV.100-200nm;src.net
BKGRND_MAG_NUV mag/arcsec^2 NUV sky background surface brightness phot.mag;em.UV.200-300nm;src.net
CLASS_STAR - NUV Sextractor star/galaxy classifier output meta.code;em.UV.200-300nm
DEC deg Declination (J2000) pos.eq.dec
EFF_EXPTIME_FUV s FUV effective exposure time (relative response) obs.exposure;em.UV.100-200nm
EFF_EXPTIME_NUV s NUV effective exposure time (relative response) obs.exposure;em.UV.200-300nm
EXPTIME_FUV s FUV exposure time of tile obs.exposure;em.UV.100-200nm
EXPTIME_NUV s NUV exposure time of tile obs.exposure;em.UV.200-300nm
FLAGS_FUV - FUV Sextraxtor extraction flags meta.code;em.UV.100-200nm
FLAGS_NUV - NUV Sextraxtor extraction flags meta.code;em.UV.200-300nm
FLUX20_RADIUS_FUV arcsec FUV 20 percent fraction-of-light radius -
FLUX20_RADIUS_NUV arcsec NUV 20 percent fraction-of-light radius -
FLUX50_RADIUS_FUV arcsec FUV 50 percent fraction-of-light radius -
FLUX50_RADIUS_NUV arcsec NUV 50 percent fraction-of-light radius -
FLUX80_RADIUS_FUV arcsec FUV 80 percent fraction-of-light radius -
FLUX80_RADIUS_NUV arcsec NUV 80 percent fraction-of-light radius -
FLUX90_RADIUS_FUV arcsec FUV 90 percent fraction-of-light radius -
FLUX90_RADIUS_NUV arcsec NUV 90 percent fraction-of-light radius -
FLUX95_RADIUS_FUV arcsec FUV 95 percent fraction-of-light radius -
FLUX95_RADIUS_NUV arcsec NUV 95 percent fraction-of-light radius -
FLUXERR_D12p0_FUV microJy FUV flux error in 12.0 arcsec (8 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D12p0_NUV microJy NUV flux error in 12.0 arcsec (8 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_D18p0_FUV microJy FUV flux error in 18.0 arcsec (12 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D18p0_NUV microJy NUV flux error in 18.0 arcsec (12 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_D25p5_FUV microJy FUV flux error in 25.5 arcsec (17 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D25p5_NUV microJy NUV flux error in 25.5 arcsec (17 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_D34p5_FUV microJy FUV flux error in 34.5 arcsec (23 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D34p5_NUV microJy NUV flux error in 34.5 arcsec (23 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_D3p0_FUV microJy FUV flux error in 3.0 arcsec (2 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D3p0_NUV microJy NUV flux error in 3.0 arcsec (2 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_D4p5_FUV microJy FUV flux error in 4.5 arcsec (3 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D4p5_NUV microJy NUV flux error in 4.5 arcsec (3 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_D7p5_FUV microJy FUV flux error in 7.5 arcsec (5 pixel) diameter aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_D7p5_NUV microJy NUV flux error in 7.5 arcsec (5 pixel) diameter aperture phot.flux;em.UV.200-300nm;stat.error
FLUXERR_FUV microJy FUV flux error using NUV aperture phot.flux;em.UV.100-200nm;stat.error
FLUXERR_NUV microJy NUV flux error phot.flux;em.UV.200-300nm;stat.error
FLUX_D12p0_FUV microJy FUV flux in 12.0 arcsec (8 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D12p0_NUV microJy NUV flux in 12.0 arcsec (8 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_D18p0_FUV microJy FUV flux in 18.0 arcsec (12 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D18p0_NUV microJy NUV flux in 18.0 arcsec (12 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_D25p5_FUV microJy FUV flux in 25.5 arcsec (17 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D25p5_NUV microJy NUV flux in 25.5 arcsec (17 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_D34p5_FUV microJy FUV flux in 34.5 arcsec (23 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D34p5_NUV microJy NUV flux in 34.5 arcsec (23 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_D3p0_FUV microJy FUV flux in 3.0 arcsec (2 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D3p0_NUV microJy NUV flux in 3.0 arcsec (2 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_D4p5_FUV microJy FUV flux in 4.5 arcsec (3 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D4p5_NUV microJy NUV flux in 4.5 arcsec (3 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_D7p5_FUV microJy FUV flux in 7.5 arcsec (5 pixel) diameter aperture phot.flux;em.UV.100-200nm
FLUX_D7p5_NUV microJy NUV flux in 7.5 arcsec (5 pixel) diameter aperture phot.flux;em.UV.200-300nm
FLUX_FUV microJy FUV calibrated flux using NUV aperture phot.flux;em.UV.100-200nm
FLUX_MAX_FUV microJy FUV peak flux above background phot.flux;em.UV.100-200nm
FLUX_MAX_NUV microJy NUV peak flux above background phot.flux;em.UV.200-300nm
FLUX_NUV microJy NUV calibrated flux phot.flux;em.UV.200-300nm
FOV_RADIUS deg Distance of object from centre of FoV pos.angDistance
FWHM_FUV arcsec FUV FWHM assuming a gaussian core phys.size;em.UV.100-200nm
FWHM_NUV arcsec NUV FWHM assuming a gaussian core phys.size;em.UV.200-300nm
GGOID - GALEX Global Object ID meta.id
GLAT deg Galactic latitude pos.galactic.lat
GLON deg Galactic longitude pos.galactic.lon
HP_PIXEL - HEALPix pixel on sky coverage maps on GALEX-GAMA web site (nside = 16384; nested) -
MAGERR_D12p0_FUV mag FUV AB magnitude error in 12.0 arcsec (8 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D12p0_NUV mag NUV AB magnitude error in 12.0 arcsec (8 pixel) diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_D18p0_FUV mag FUV AB magnitude error in 18.0 arcsec (12 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D18p0_NUV mag NUV AB magnitude error in 18.0 arcsec (12 pixel) diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_D25p5_FUV mag FUV AB magnitude error in 25.5 arcsec (17 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D25p5_NUV mag NUV AB magnitude error in 25.5 arcsec (17 pixel) diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_D34p5_FUV mag FUV AB magnitude error in 34.5 arcsec (23 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D34p5_NUV mag NUV AB magnitude error in 34.5 arcsec (23 pixel) diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_D3p0_FUV mag FUV AB magnitude error in 3.0 arcsec (2 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D3p0_NUV mag NUV AB magnitude error in 3.0 arcsec (2 pixel)diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_D4p5_FUV mag FUV AB magnitude error in 4.5 arcsec (3 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D4p5_NUV mag NUV AB magnitude error in 4.5 arcsec (3 pixel) diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_D7p5_FUV mag FUV AB magnitude error in 7.5 arcsec (5 pixel) diameter aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_D7p5_NUV mag NUV AB magnitude error in 7.5 arcsec (5 pixel) diameter aperture phot.mag;em.UV.200-300nm;stat.error
MAGERR_FUV mag FUV calibrated AB Kron magnitude error using NUV aperture phot.mag;em.UV.100-200nm;stat.error
MAGERR_NUV mag NUV calibrated AB Kron magnitude error phot.mag;em.UV.200-300nm;stat.error
MAG_D12p0_FUV mag FUV AB magnitude in 12.0 arcsec (8 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D12p0_NUV mag NUV AB magnitude in 12.0 arcsec (8 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_D18p0_FUV mag FUV AB magnitude in 18.0 arcsec (12 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D18p0_NUV mag NUV AB magnitude in 18.0 arcsec (12 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_D25p5_FUV mag FUV AB magnitude in 25.5 arcsec (17 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D25p5_NUV mag NUV AB magnitude in 25.5 arcsec (17 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_D34p5_FUV mag FUV AB magnitude in 34.5 arcsec (23 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D34p5_NUV mag NUV AB magnitude in 34.5 arcsec (23 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_D3p0_FUV mag FUV AB magnitude in 3.0 arcsec (2 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D3p0_NUV mag NUV AB magnitude in 3.0 arcsec (2 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_D4p5_FUV mag FUV AB magnitude in 4.5 arcsec (3 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D4p5_NUV mag NUV AB magnitude in 4.5 arcsec (3 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_D7p5_FUV mag FUV AB magnitude in 7.5 arcsec (5 pixel) diameter aperture phot.mag;em.UV.100-200nm
MAG_D7p5_NUV mag NUV AB magnitude in 7.5 arcsec (5 pixel) diameter aperture phot.mag;em.UV.200-300nm
MAG_FUV mag FUV calibrated AB Kron magnitude using NUV aperture phot.mag;em.UV.100-200nm
MAG_NUV mag NUV calibrated AB Kron magnitude phot.mag;em.UV.200-300nm
NAME - Object IAU format name meta.id
NUMBER_MCAT - Running object number from GALEX MCAT file meta.id
POSANG deg Position angle (east of north) pos.posAng
POSANGERR deg Position angle error pos.posAng;stat.error
POSERR arcsec Position error stat.error
RA deg Right Ascension (J2000) pos.eq.ra
S2N_FUV - FUV signal-to-noise from flux value (NB: can become negative for negative flux) stat.snr;em.UV.100-200nm
S2N_NUV - NUV signal-to-noise from flux value stat.snr;em.UV.200-300nm
SEMIMAJOR arcsec Semimajor axis phys.size.radius
SEMIMAJORERR arcsec Semimajor axis error phys.size.radius;stat.error
SEMIMINOR arcsec Semiminor axis phys.size.radius
SEMIMINORERR arcsec Semiminor axis error phys.size.radius;stat.error
TILE - GALEX tile name meta.id
TILENUM - GALEX tile number meta.number
XPEAK_IMAGE pixel Pixel position of the brightest NUV pixel on intensity maps -
X_IMAGE pixel Object pixel position on intensity maps -
YPEAK_IMAGE pixel Pixel position of the brightest NUV pixel on intensity maps -
Y_IMAGE pixel Object pixel position on intensity maps -
GalexSimpleMatch
name: GalexSimpleMatch | type: table | 2012-11-13 | Ellen Andrae [javascript protected email address] | version v02 |
This catalogue contains the result of a simple nearest neighbour match between InputCatA and GalexPhot, listing only objects included in DR2. GAMA DR2 objects without a GALEX nearest neighbour within a distance of 4 arcsec are considered unmatched and are not included in this catalogue.
GalexPhotometry
GalexSimpleMatch
v02
2012-11-13
Ellen Andrae

This catalogue contains the result of a simple nearest neighbour match
between InputCatA (the GAMA I SDSS-based input catalogue) and
GalexPhot. For each GAMA DR2 object this catalogue lists its nearest
neighbour GALEX object provided that the distance between the two is
less than 4 arcsec. GAMA DR2 objects without a GALEX nearest neighbour
within a distance of 4 arcsec are considered unmatched and are not
included in this catalogue. Refer to the table GalexObsInfo for
detection limits and to distinguish between GAMA objects that were not
detected in the GALEX data and those that were not covered by GALEX.

To obtain the properties of a given GAMA object's nearest neighbour
GALEX object simply join this table with the table GalexPhot on the
column GGOID.

Note that the resolution of the GALEX imaging is ~5 arcsec. This
obviously means that a given GALEX detection in GalexPhot may not
represent the UV flux of a single GAMA object (defined in the optical)
but the joint UV flux of multiple GAMA objects. In these cases it
would be incorrect to assign all of the GALEX flux to any single GAMA
object. Furthermore, doing so would introduce an environmental bias:
GAMA objects with many other close-by objects would be more likely to
be associated with a GALEX detection than isolated GAMA objects.

Hence, as a quality indicator of the match, the number of GALEX
objects within 4 arcsec distance to the GAMA objects is listed in
column NMATCH4. The column MANY2ONE gives the number of GAMA objects
this GALEX object has been matched to. If one of these two columns is
larger than 1, this must be considered a multiple match and we
recommend the use of the BEST_FLUX_XXX columns in GalexMain instead of
the nearest neighbour fluxes.

Further GALEX objects within a matching radius of 20 arcsec are also
listed (in columns GNEIGHBOR_*) to indicate potential multiple
matches.

Address this table as gama_dr2.GalexSimpleMatch
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - Unique ID of GAMA object meta.id
FUVMATCH - Flag indicating whether matched GALEX source has FUV flux with S/N >=2.5 (-1=no FUV data) meta.code;em.UV.100-200nm
GGOID - Global Object ID of nearest neighbour GALEX object meta.id
GNEIGHBOR_DIST - String list of distances to all GALEX sources within 20 arcsec -
GNEIGHBOR_NAME - String list of names of all GALEX sources within 20 arcsec -
MANY2ONE - Number of GAMA objects the GALEX object is matched to meta.number
NMATCH4 - Number of GALEX objects found within 4 arcsec of GAMA object meta.number
NN_DIST arcsec Distance between GAMA object and nearest neighbour GALEX object pos.angDistance
OBJID - SDSS objid of GAMA object meta.id
GroupFinding
name: GroupFinding | type: group | 2012-07-26 | Aaron Robotham [javascript protected email address] | version v05 |
This DMU provides the GAMA Galaxy Group Catalogue (G3C).
GroupFinding
2012-07-26
Aaron Robotham

The GAMA Galaxy Group Catalogue (G3C) is one of the major data
products for the GAMA project. At the most basic level it is a
Friends-of-Friends (FoF) group catalogue that has been run on GAMA
survey style mocks (put together by Peder Norberg and various
collaborators in Durham) to test the quality of the grouping and then
run on the real GAMA data in order to extract our best effort
groups. The details of the process are discussed extensively in
Robotham et al. 2011 (MNRAS).

Note that this release only covers the GAMA G15 survey region, as this
is the only region for which DR2 includes data down to the survey
limit (r < 19.4 mag).

This DMU necessarily produces a large number of catalogues and it
might seem over-whelming at a glance, but a lot of effort has gone
into to simplifying the outputs as much as possible, and limiting the
products to the most useful subset of data. The major products are
split into the mock groups and the observed GAMA groups. Below we
discuss the catalogues contained in the DMU. For most user purposes
G3CGal and G3CFoFGroup will be the most useful catalogues.

For all catalogues the null value is -999 unless stated otherwise.

The GroupFinding DMU does not have many catalogue dependencies, it
only really needs SDSS photometry, RA, DEC, and redshift. The DMUs
used to create the GroupFinding DMU are:

Mocks v02 (not a GAMA accessible DMU)
SpecCat v06
InputCat v11

Note that the SpecCat and InputCat versions used here are slightly
earlier versions than the ones being released in DR2 (v08 and v16,
respectively). The difference between these versions is the addition
of more re-redshifting data (see the notes of the SpecCat DMU for an
explanation of "re-redshifting"). That means that for some objects the
redshift and redshift quality used in this DMU will be different from
those listed by the SpecCat DMU or in TilingCat.

-----------------------------------------------------------------------

G3C GAMA group catalogues:

G3CGal:
List of all galaxies that were used for GAMA grouping. The sample
covers the G15 survey region only (r < 19.4 mag) and was selected to
be between 0.01 < z < 0.5 to avoid LF and distance uncertainties at
very low redshift. This catalogue also contains the group references
for grouped galaxies.

G3CFoFGroup:
List of FoF group properties. The GroupID references in G3CGal link to
this catalogue.

G3CLink:
List of all galaxy-galaxy links found when running the FoF that
created G3CFoFGroup. This is useful if the user wished to know which
galaxies are linked the most with other galaxies within a group, or to
find the most tenuously associated galaxies within a group.

G3CGalsInPair:
A list of all galaxies that are paired with another galaxy within a
projected physical separation of 50 kpc/h and a velocity separation of
1,000 km/s. Users should be aware that pairs are listed in both
gal1-gal2 and gal2-gal1 combinations, so the number of pairs is half
the number of links in this catalogue.

-------------------------------------------------------------------------

G3C Mock catalogues:

9 mock catalogues were created in all, where each mock catalogue
covers not only the G15 region as is the case for the real data above,
but contains a complete analogue of the full GAMA I survey - i.e. 3
regions of 12 x 4 deg^2 out to redshift 0.5. Since the 3 regions have
the same size and shape this means that the mocks provide a total of 9
x 3 = 27 comparison volumes. The mocks are limited to r < 19.4 mag as
are the real data. Each catalogue below contains all 9 mock volumes,
with a column specifying the relevant volume number.

G3CMockGal:
List of all galaxies that were used for mock grouping. The sample was
selected to be between 0.01 < z < 0.5 to be consistent with the cuts
made for the real data. This catalogue also contains the group
references for grouped galaxies.

G3CMockFoFGroup:
List of FoF group properties for the mocks. The GroupID references in
G3CMockGal link to this catalogue.

G3CMockHaloGroup:
List of halo group properties for the mocks. "Halo group" refers to
the intrinsic group of galaxies that are given in the mock catalogues,
so these groups can be considered to be "the truth" for comparison
purposes. The HaloID references in G3CMockGal link to this
catalogue.

G3CMockLink:
List of all mock galaxy-galaxy links found when running the FoF that
created G3CMockFoFGroup. This is useful if the user wishes to know
which galaxies are linked the most with other galaxies within a group,
or to find the most tenuously associated galaxies within a group.

G3CMockGalsInPair:
A list of all mock galaxies that are paired with another mock galaxy
within a projected physical separation of 50 kpc/h and a velocity
separation of 1,000 km/s. Users should be aware that pairs are listed
in both gal1-gal2 and gal2-gal1 combinations, so the number of pairs
is half the number of links in this catalogue.

G3CFoFGroup
name: G3CFoFGroup | type: table | 2011-09-14 | Aaron Robotham [javascript protected email address] | version v04 |
This is a catalogue of G3C GAMA group properties. G15 only.
GroupFinding
G3CFoFGroup
v04
2011-09-14
Aaron Robotham

The cosmology used is H_0=100 km/s/Mpc, Omega_L=0.75,Omega_M=0.25.

All r-band derived quantities use Rpetro in G3CGal.

General notes:
=============

a. To obtain a proper total dynamical mass calibration for the groups
the user should read section 4.3 in the accompanying paper
(Robotham et al. 2011). In the present catalogue, MassProxy
is listed with A=1. For Nfof>=5 the suggested best median global
correction for the *user to apply* is A=10.0. This is used in the
MassA column.

b. To obtain a proper total luminosity calibration for the groups the
user should read section 4.4 in the accompanying paper (Robotham et
al. 2011). In the present catalogue, TotFluxProxy is listed
with B=1. For Nfof>=5 the suggested best median global correction
for the *user to apply* is B=1.04. This is used in the MassB
column.

c. To obtain a proper total (dynamical) mass calibration for the
groups from their total luminosity the user should calibrate the
luminosity-mass relation independently for the data and the
mocks. This calibration should be done using TotFluxProxy (with the
appropriate B factor) and MassProxy (with the appropriate A
factor). We would generally recommend a median unbiased calibration,
split as function of Nfof and Zfof as has been done in Robotham
et al. (2011) for most group properties.

d. To avoid any edge effects, only groups with GroupEdge=1 should be
selected. To create a volume limited sample just select the RA and
DEC ranges that don't include any groups that have a GroupEdge less
than 1.

e. The final four columns (MassA, MassAfunc, LumMassB and LumMassBfunc)
contain the best effort group mass/luminosity scalings. The
functional form using the group redshift and multiplicity has
the "func" suffix, and the global median correction does not.
Address this table as gama_dr2.G3CFoFGroup
Name Unit Description UCD (hover for description)
Name Unit Description UCD
AxAng deg Angle of the group major axis on the sky (N -> E = 0 -> 90) using the Carter & Metcalfe (1984) algorithm (requires 3 or more members, so -999 otherwise) -
AxRat - Axial ratio of the group using the Carter & Metcalfe (1984) algorithm (requires 3 or more members, so -999 otherwise) -
BCGCATAID - GAMA ID of BCG meta.id
BCGDec deg Dec of BCG (J2000) pos.eq.dec
BCGRA deg RA of BCG (J2000) pos.eq.ra
CenDec deg Dec of group for a r-band luminosity weighted CoM of the system (J2000) pos.eq.dec
CenRA deg RA of group for a r-band luminosity weighted CoM of the system (J2000) pos.eq.ra
GroupEdge - Fraction of the group within the survey volume, as estimated from IterCen and Rad100 -
GroupID - Unique group ID, as used in G3CGal meta.id;meta.main
IterCenCATAID - GAMA ID of the iterative central galaxy (prefered position of the group centre, see Robotham et al. 2011 section 4.2) meta.id
IterCenDEC deg Dec of the iterative central galaxy (J2000) pos.eq.dec
IterCenRA deg RA of the iterative central galaxy (J2000) pos.eq.ra
IterCenZ - Redshift of the iterative central galaxy -
LinkStrenComb - Link strength combined, average of LinkStrenProj*LinkStrenZ for all the links in the group (0<=LinkStrenComb<=1) -
LinkStrenProj - Link strength in projection, average projected FoF link relative to the separation allowed by the FoF algorithm (0<=LinkStrenProj<=1) -
LinkStrenRad - Link strength radially, average radial FoF link relative to the separation allowed by the FoF algorithm (0<=LinkStrenZ<=1) -
LinkTot - Total number of FoF links in the system -
LumB Lsun TotFluxProxy times the global B factor required to get a median unbaised halo mass estimate (B=1.04, see Robotham et al. 2011 section 4.4 for details) -
LumBfunc Lsun TotFluxProxy times the functional B factor which is a function of Nfof and IterCenZ (see Robotham et al. 2011 section 4.4 for details) -
MassA Msun Mass proxy times the global A factor required to get a median unbaised halo mass estimate (A=10.0, see Robotham et al. 2011 section 4.3 for details) -
MassAfunc Msun Mass proxy times the functional A factor which is a function of Nfof and IterCenZ (see Robotham et al. 2011 section 4.3 for details) -
MassProxy Msun Proxy for dynamical group mass estimated via M propto Rad50 * VelDisp^2 . Value listed corresponds to A=1 in Eq. 18 of Robotham et al. (2011), i.e. calibrated mass is given by A*M, with A the scaling factor described in section 4.3 of Robotham et al. (2011) -
Modality - The modality of the system: (1+VelSkew^2)/(3+VelKurt^2). This will be 1/3 for a normal distribution and 0.555 for a uniform. -
Nfof - Group multiplicity -
Rad100 Mpc/h Group radius defined by the most distant group member, based on the projected distance away from IterCenID -
Rad1Sig Mpc/h Group radius defined by the 68th percentile group member, based on the projected distance away from IterCenID -
Rad50 Mpc/h Group radius defined by the 50th percentile group member, based on the projected distance away from IterCenID -
RadKurt - Unbiased kurtosis of the radial distribution of galaxies based on the projected distance to IterCen -
RelDen - Relative galaxy space density (w.r.t. the SWML prediction) within a cylinder of radius 1.5 Mpc/h and length 18Mpc/h centred on IterCenID. -
Rgap mag Apparent r-band magnitude gap between BCG and second brightest group member -
SymKS - KS test of the uniformity of groups once corrected for the axial-ratio; an elliptical group has an average p-value of 0.5 (requires 3 or more members, so -999 otherwise) -
TotFluxProxy Lsun Proxy for group total r-band luminosity down to M_r - 5 log_10 h = -14 in solar luminosities. It is based on the total observed r-band flux and the fraction of light (as estimated from the global galaxy LF) observable at the group redshift. Value listed corresponds to B=1 in Eq. 21 of Robotham et al. (2011) -
TotRmag mag r-band absolute magnitude of the group, obtained by adding up the r-band luminosities of its members -
URL_IMG - URL of the group`s image meta.ref.url;meta.file
VelDisp km/s Group velocity dispersion, corrected for the total group velocity dispersion error (VelErr); set to zero if VelErr>VelDispRaw (see eq. 17 in Robotham et al. 2011) -
VelDispRaw km/s Raw group velocity dispersion -
VelErr km/s Total group velocity error -
VelKurt - Unbiased kurtosis of the galaxy velocities (requires 4 or more members, so -999 otherwise) -
VelSkew - Unbiased skew of the galaxy velocities (requires 3 or more members, so -999 otherwise) -
Zcomp - Average redshift completeness of the group: for each group member the redshift completeness within a projected 1.5 Mpc/h radius (at the position of the galaxy) is estimated and then averaged over all group members to provide ZComp -
Zfof - Median redshift of the group -
G3CGal
name: G3CGal | type: table | 2012-07-26 | Aaron Robotham [javascript protected email address] | version v05 |
Catalogue of all GAMA galaxies used in the G3C. G15 only.
Address this table as gama_dr2.G3CGal
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - GAMA ID meta.id;meta.main
DEC deg Declination (J2000) pos.eq.dec
DM_100_25_75 mag Distance modulus using H0=100 km/s/Mpc, Omega_m=0.25 and Omega_L=0.75 -
GroupID - GroupID of the group this galaxy belongs to as listed in G3CFoFGroup, 0 is un-grouped meta.id
RA deg Right Ascension (J2000) pos.eq.ra
Rpetro mag Petrosian apparent r-band magnitude (AB, extinction corrected) [GAMA selection magnitude] -
SURVEY_CODE - Source of the redshift. See the notes of table TilingCat in the InputCat DMU for full details -
SigErr km/s Velocity uncertainty (on redshift): assumed to be 30 km/s for SDSS, 50 km/s for GAMA and 80 km/s for 2dFGRS -
Z - Heliocentric redshift -
G3CGalsInPair
name: G3CGalsInPair | type: table | 2011-09-14 | Aaron Robotham [javascript protected email address] | version v04 |
Catalogue of galaxies that live in pairs (thus gal1-gal2 and gal2-gal1 combinations are both listed). Galaxy pairs are required to be within 50 kpc/h in physical separation and 1000 km/s in velocity separation. G15 only.
Address this table as gama_dr2.G3CGalsInPair
Name Unit Description UCD (hover for description)
Name Unit Description UCD
Gal1CATAID - GAMA ID of galaxy 1 in G3CGal meta.id
Gal2CATAID - GAMA ID of galaxy 2 in G3CGal meta.id
PairID - Unique pair ID for catalogue meta.id;meta.main
SepProjAng kpc/h Physical projected separation between galaxy 1 and galaxy 2 -
SepVel km/s Velocity separation of galaxy 1 and galaxy 2 -
G3CMockFoFGroup
name: G3CMockFoFGroup | type: table | 2011-09-14 | Aaron Robotham [javascript protected email address] | version v04 |
This is a catalogue of G3C mock FoF group properties.
GroupFinding
G3CMockFoFGroup
v04
2011-09-14
Aaron Robotham

The cosmology used is H_0=100*h,Omega_L=0.75,Omega_M=0.25.

All r-band derived quantities use Rpetro in G3CMockGal.

General notes:
=============

a. To obtain a proper total dynamical mass calibration for the groups
the user should read section 4.3 in the accompanying paper
(Robotham et al. 2011). In the present catalogue, MassProxy
is listed with A=1. For Nfof>=5 the suggested best median global
correction for the *user to apply* is A=10.0. This is used in the
MassA column.

b. To obtain a proper total luminosity calibration for the groups the
user should read section 4.4 in the accompanying paper (Robotham et
al. 2011). In the present catalogue, TotFluxProxy is listed
with B=1. For Nfof>=5 the suggested best median global correction
for the *user to apply* is B=1.04. This is used in the MassB
column.

c. To obtain a proper total (dynamical) mass calibration for the
groups from their total luminosity the user should calibrate the
luminosity-mass relation independently for the data and the
mocks. This calibration should be done using TotFluxProxy (with the
appropriate B factor) and MassProxy (with the appropriate A
factor). We would generally recommend a median unbiased calibration,
split as function of Nfof and Zfof as has been done in Robotham
et al. (2011) for most group properties.

d. To avoid any edge effects, only groups with GroupEdge=1 should be
selected. To create a volume limited sample just select the RA and
DEC ranges that don't include any groups that have a GroupEdge less
than 1.

e. The final four columns (MassA, MassAfunc, LumMassB and LumMassBfunc)
contain the best effort group mass/luminosity scalings. The
functional form using the group redshift and multiplicity has
the "func" suffix, and the global median correction does not.
Address this table as gama_dr2.G3CMockFoFGroup
Name Unit Description UCD (hover for description)
Name Unit Description UCD
AxAng deg Angle of the group major axis on the sky (N -> E = 0 -> 90) using the Carter & Metcalfe (1984) algorithm (requires 3 or more members, so -999 otherwise) -
AxRat - Axial ratio of the group using the Carter & Metcalfe (1984) algorithm (requires 3 or more members, so -999 otherwise) -
BCGDec deg Dec of BCG (J2000) pos.eq.dec
BCGGalID - GalID of BCG meta.id
BCGRA deg RA of BCG (J2000) pos.eq.ra
CenDec deg Dec of group for a r-band luminosity weighted CoM of the system (J2000) pos.eq.dec
CenRA deg RA of group for a r-band luminosity weighted CoM of the system (J2000) pos.eq.ra
GroupEdge - Fraction of the group within the survey volume, as estimated from IterCen and Rad100 -
GroupID - Unique group ID, as referred to by G3CMockGal meta.id;meta.main
IterCenDEC deg Dec of the iterative central galaxy (J2000) pos.eq.dec
IterCenGalID - GalID of the iterative central galaxy (prefered position of the group centre, see Robotham et al. 2011 section 4.2) meta.id
IterCenRA deg RA of the iterative central galaxy (J2000) pos.eq.ra
IterCenZ - Redshift of the iterative central galaxy -
LinkStrenComb - Link strength combined, average of LinkStrenProj*LinkStrenZ for all the links in the group (0<=LinkStrenComb<=1) -
LinkStrenProj - Link strength in projection, average projected FoF link relative to the separation allowed by the FoF algorithm (0<=LinkStrenProj<=1) -
LinkStrenRad - Link strength radially, average radial FoF link relative to the separation allowed by the FoF algorithm (0<=LinkStrenZ<=1) -
LinkTot - Total number of FoF links in the system -
LumB Lsun TotFluxProxy times the global B factor required to get a median unbaised halo mass estimate (B=1.04, see Robotham et al. 2011 section 4.4 for details) -
LumBfunc Lsun TotFluxProxy times the functional B factor which is a function of Nfof and IterCenZ (see Robotham et al. 2011 section 4.4 for details) -
MassA Msun Mass proxy times the global A factor required to get a median unbaised halo mass estimate (A=10.0, see Robotham et al. 2011 section 4.3 for details) -
MassAfunc Msun Mass proxy times the functional A factor which is a function of Nfof and IterCenZ (see Robotham et al. 2011 section 4.3 for details) -
MassProxy Msun Proxy for dynamical group mass estimated via M propto Rad50 * VelDisp^2 . Value listed corresponds to A=1 in Eq. 18 of Robotham et al. (2011), i.e. calibrated mass is given by A*M, with A the scaling factor described in section 4.3 of Robotham et al. (2011) -
Modality - The modality of the system: (1+VelSkew^2)/(3+VelKurt^2). This will be 1/3 for a normal distribution and 0.555 for a uniform. -
Nfof - Group multiplicity -
Rad100 Mpc/h Group radius defined by the most distant group member, based on the projected distance away from IterCenID -
Rad1Sig Mpc/h Group radius defined by the 68th percentile group member, based on the projected distance away from IterCenID -
Rad50 Mpc/h Group radius defined by the 50th percentile group member, based on the projected distance away from IterCenID -
RadKurt - Unbiased kurtosis of the radial distribution of galaxies based on the projected distance to IterCen -
RelDen - Relative galaxy space density (w.r.t. the SWML prediction) within a cylinder of radius 1.5 Mpc/h and length 18Mpc/h centred on IterCenID. -
Rgap mag Apparent r-band magnitude gap between BCG and second brightest group member -
SymKS - KS test of the uniformity of groups once corrected for the axial-ratio; an elliptical group has an average p-value of 0.5 (requires 3 or more members, so -999 otherwise) -
TotFluxProxy Lsun Proxy for group total r-band luminosity down to M_r - 5 log_10 h = -14 in solar luminosities. It is based on the total observed r-band flux and the fraction of light (as estimated from the global galaxy LF) observable at the group redshift. Value listed corresponds to B=1 in Eq. 21 of Robotham et al. (2011) -
TotRmag mag r-band absolute magnitude of the group, obtained by adding up the r-band luminosities of its members -
VelDisp km/s Group velocity dispersion, corrected for the total group velocity dispersion error (VelErr); set to zero if VelErr>VelDispRaw (see eq. 17 in Robotham et al. 2011) -
VelDispRaw km/s Raw group velocity dispersion -
VelErr km/s Total group velocity error -
VelKurt - Unbiased kurtosis of the galaxy velocities (requires 4 or more members, so -999 otherwise) -
VelSkew - Unbiased skew of the galaxy velocities (requires 3 or more members, so -999 otherwise) -
Volume - The mock volume number -
Zfof - Median redshift of the group -
G3CMockGal
name: G3CMockGal | type: table | 2011-09-14 | Aaron Robotham [javascript protected email address] | version v04 |
Catalogue of all mock galaxies used in the G3C.
GroupFinding
G3CMockGal
v04
2011-09-14
Aaron Robotham

MillSimID is a unique group/halo id, based on the information listed
in the variables "ivol", "jm", "nh_id" (AKA "nbody_halo_id") and
"idrep" in the Durham Millennium Simulation lightcone mocks:

ivol*d_jm_nh_id_idrep + jm * d_nh_id_idrep + nbody_halo_id * d_idrep + idrep

idrep_max=2**16
nh_id_max=2**18
jm_max=2**15
d_idrep=idrep_max
d_nh_id_idrep=d_idrep*nh_id_max
d_jm_nh_id_idrep=d_nh_id_idrep*jm_max

Using MillSimID allows users to unambiguosuly identify the galaxy
listed in the original Durham Millennium Simulation catalogues.
Address this table as gama_dr2.G3CMockGal
Name Unit Description UCD (hover for description)
Name Unit Description UCD
DEC deg Declination (J2000) pos.eq.dec
DM_100_25_75 mag Distance modulus -
GalID - Mock galaxy ID meta.id;meta.main
GroupID - GroupID of the group this galaxy belongs to as listed in G3CMockFoFGroup, 0 is un-grouped meta.id
HaloID - HaloID of the halo group this galaxy belongs to as listed in G3CMockHaloGroup -
MillSimID - A unique group/halo id used in the Millennium Simulation, see notes for details -
RA deg Right Ascension (J2000) pos.eq.ra
Rpetro mag Petrosian apparent r-band magnitude (AB, extinction corrected) [GAMA selection magnitude] -
SelID - Galaxy listed as #idsel used in the Millennium Simulation, see notes for details -
Volume - The mock volume number -
Zspec - Heliocentric redshift -
G3CMockGalsInPair
name: G3CMockGalsInPair | type: table | 2011-09-14 | Aaron Robotham [javascript protected email address] | version v04 |
Catalogue of galaxies that live in pairs (thus gal1-gal2 and gal2-gal1 combinations are both listed). Galaxy pairs are required to be within 50 kpc/h in physical separation and 1000 km/s in velocity separation.
Address this table as gama_dr2.G3CMockGalsInPair
Name Unit Description UCD (hover for description)
Name Unit Description UCD
Gal1GalID - GalID of galaxy 1 in G3CMockGal meta.id
Gal2GalID - GalID of galaxy 2 in G3CMockGal meta.id
PairID - Unique pair ID for catalogue meta.id;meta.main
SepProjAng kpc/h Physical projected separation between galaxy 1 and galaxy 2 -
SepVel km/s Velocity separation of galaxy 1 and galaxy 2 -
Volume - The mock volume number -
G3CMockHaloGroup
name: G3CMockHaloGroup | type: table | 2011-09-14 | Aaron Robotham [javascript protected email address] | version v04 |
This is a catalogue of G3C mock halo group properties. These are the intrinsic groups found in the mocks.
GroupFinding
G3CMockHaloGroup
v04
2011-09-14
Aaron Robotham

This catalogue contains the "true" groups found in the mock
simulations. This can be used for comparison purposes to test the
quality of the FoF grouping.

The cosmology used is H_0=100*h,Omega_L=0.75,Omega_M=0.25.

All r-band derived quantities use Rpetro in G3CMockGal.

General notes:
=============

a. To obtain a proper total dynamical mass calibration for the groups
the user should read section 4.3 in the accompanying paper
(Robotham et al. 2011). In the present catalogue, MassProxy
is listed with A=1. For Nfof>=5 the suggested best median global
correction for the *user to apply* is A=10.0. This is used in the
MassA column.

b. To obtain a proper total luminosity calibration for the groups the
user should read section 4.4 in the accompanying paper (Robotham et
al. 2011). In the present catalogue, TotFluxProxy is listed
with B=1. For Nfof>=5 the suggested best median global correction
for the *user to apply* is B=1.04. This is used in the MassB
column.

c. To obtain a proper total (dynamical) mass calibration for the
groups from their total luminosity the user should calibrate the
luminosity-mass relation independently for the data and the
mocks. This calibration should be done using TotFluxProxy (with the
appropriate B factor) and MassProxy (with the appropriate A
factor). We would generally recommend a median unbiased calibration,
split as function of Nfof and Zfof as has been done in Robotham
et al. (2011) for most group properties.

d. To avoid any edge effects, only groups with GroupEdge=1 should be
selected. To create a volume limited sample just select the RA and
DEC ranges that don't include any groups that have a GroupEdge less
than 1.

e. The final four columns (MassA, MassAfunc, LumMassB and LumMassBfunc)
contain the best effort group mass/luminosity scalings. The
functional form using the group redshift and multiplicity has
the "func" suffix, and the global median correction does not.
Address this table as gama_dr2.G3CMockHaloGroup
Name Unit Description UCD (hover for description)
Name Unit Description UCD
AxAng deg Angle of the group major axis on the sky (N -> E = 0 -> 90) using the Carter & Metcalfe (1984) algorithm (requires 3 or more members, so -999 otherwise) -
AxRat - Axial ratio of the group using the Carter & Metcalfe (1984) algorithm (requires 3 or more members, so -999 otherwise) -
BCGDec deg Dec of BCG (J2000) pos.eq.dec
BCGGalID - GalID of BCG meta.id
BCGRA deg RA of BCG (J2000) pos.eq.ra
CenDec deg Dec of group for a r-band luminosity weighted CoM of the system (J2000) pos.eq.dec
CenRA deg RA of group for a r-band luminosity weighted CoM of the system (J2000) pos.eq.ra
GroupEdge - Fraction of the group within the survey volume, as estimated from IterCen and Rad100 -
HaloID - Unique halo ID, as referred to by G3CMockGal meta.id;meta.main
HaloMass Msun/h The dark matter halo mass for the group halo in the Millennium simulation -
IterCenDEC deg Dec of the iterative central galaxy (J2000) pos.eq.dec
IterCenGalID - GalID of the iterative central galaxy (prefered position of the group centre, see Robotham et al. 2011 section 4.2) meta.id
IterCenRA deg RA of the iterative central galaxy (J2000) pos.eq.ra
IterCenZ - Redshift of the iterative central galaxy -
LumB Lsun TotFluxProxy times the global B factor required to get a median unbaised halo mass estimate (B=1.04, see Robotham et al. 2011 section 4.4 for details) -
LumBfunc Lsun TotFluxProxy times the functional B factor which is a function of Nfof and IterCenZ (see Robotham et al. 2011 section 4.4 for details) -
MassA Msun Mass proxy times the global A factor required to get a median unbaised halo mass estimate (A=10.0, see Robotham et al. 2011 section 4.3 for details) -
MassAfunc Msun Mass proxy times the functional A factor which is a function of Nfof and IterCenZ (see Robotham et al. 2011 section 4.3 for details) -
MassProxy Msun Proxy for dynamical group mass estimated via M propto Rad50 * VelDisp^2 . Value listed corresponds to A=1 in Eq. 18 of Robotham et al. (2011), i.e. calibrated mass is given by A*M, with A the scaling factor described in section 4.3 of Robotham et al. (2011) -
Modality - The modality of the system: (1+VelSkew^2)/(3+VelKurt^2). This will be 1/3 for a normal distribution and 0.555 for a uniform. -
Nhalo - Group multiplicity -
Rad100 Mpc/h Group radius defined by the most distant group member, based on the projected distance away from IterCenID -
Rad1Sig Mpc/h Group radius defined by the 68th percentile group member, based on the projected distance away from IterCenID -
Rad50 Mpc/h Group radius defined by the 50th percentile group member, based on the projected distance away from IterCenID -
RadKurt - Unbiased kurtosis of the radial distribution of galaxies based on the projected distance to IterCen -
RelDen - Relative galaxy space density (w.r.t. the SWML prediction) within a cylinder of radius 1.5 Mpc/h and length 18Mpc/h centred on IterCenID. -
Rgap mag Apparent r-band magnitude gap between BCG and second brightest group member -
SymKS - KS test of the uniformity of groups once corrected for the axial-ratio; an elliptical group has an average p-value of 0.5 (requires 3 or more members, so -999 otherwise) -
TotFluxProxy Lsun Proxy for group total r-band luminosity down to M_r - 5 log_10 h = -14 in solar luminosities. It is based on TotFlux and the fraction of light (as estimated from the global galaxy LF) observable at the group redshift. Value listed corresponds to B=1 in Eq. 21 of Robotham et al. (2011) -
TotRmag mag Observed r-band absolute magnitude of the group, obtained by adding up the r-band luminosities of its members -
VelDisp km/s Group velocity dispersion, corrected for the total group velocity dispersion error (VelErr); set to zero if VelErr>VelDispRaw (see eq. 17 in Robotham et al. 2011) -
VelDispRaw km/s Raw group velocity dispersion -
VelErr km/s Total group velocity error -
VelKurt - Unbiased kurtosis of the galaxy velocities (requires 4 or more members, so -999 otherwise) -
VelSkew - Unbiased skew of the galaxy velocities (requires 3 or more members, so -999 otherwise) -
Volume - The mock volume number -
Zhalo - Median redshift of the group -
InputCat
name: InputCat | type: group | 2011-07-20 | Ivan Baldry [javascript protected email address] | version v16 |
This DMU provides various input catalogues for the spectroscopy.
InputCat
2011-07-20
Ivan Baldry

This data management unit produces various input catalogues for the
GAMA I survey regions. We expect that the table TilingCat will be of
most interest to most users.
GalacticExtinction
name: GalacticExtinction | type: table | 2011-12-08 | Joe Liske [javascript protected email address] | version v01 |
This table provides the Galactic foreground extinction in all GALEX, SDSS and UKIDSS bands for every object in InputCatA and SpStandards.
InputCat
GalacticExtinction
v01
2011-12-08
Joe Liske

This table provides the Galactic foreground extinction in all GALEX,
SDSS and UKIDSS bands for the position of every object listed in
InputCatA and SpStandards.

The extinction in each band x was calculated as
A_x = (A_x / E(B-V)) * E(B-V).

For each position in this table the value of E(B-V) was taken from the
dust maps of Schlegel et al. (1998), interpolating from the nearest 4
pixels.

The values of A_x/E(B-V) were taken from this list:

Band A_x/E(B-V)
--------------------------
GALEX
FUV 8.376
NUV 8.741
MGC
B 4.23
SDSS
u 5.155
g 3.793
r 2.751
i 2.086
z 1.479
UKIDSS
Y 1.211
J 0.889
H 0.578
K 0.360


The SDSS values were taken from Schlegel et al. (1998). These were
calculated assuming the extinction law of O'Donnell (1994) in the
optical and that of Cardelli et al. (1989) in the UV and IR, with
R_V=3.1, and a z=0 elliptical galaxy spectrum.

The GALEX values were taken from Wyder et al. (2005). These were
calculated assuming the extinction law of Cardelli et al. (1989). The
R_V value used in this calculation was not specified. In addition, no
source spectrum was used, instead the extinction law was simply
averaged over the filter.

The UKIDSS values were taken from the WFCAM Science Archive. According
to Nick Cross these values were calculated assuming the extinction law
of Cardelli et al. (1989), with R_V=3.1, and a z=0 elliptical galaxy
spectrum (i.e. exactly following the procedure of Schlegel et
al. 1998
).

The MGC value was taken from Liske et al. (2003). How this value was
calculated is lost in the mists of time.

Note that the extinction values for the SDSS bands in this table are
identical to those provided by the SDSS database (see also Stoughton
et al. 2002
).

Address this table as gama_dr2.GalacticExtinction
Name Unit Description UCD (hover for description)
Name Unit Description UCD
A_B mag Galactic extinction in MGC B band phys.absorption.gal;em.opt.B
A_FUV mag Galactic extinction in GALEX FUV band phys.absorption.gal;em.UV.100-200nm
A_H mag Galactic extinction in UKIDSS H band phys.absorption.gal;em.IR.H
A_J mag Galactic extinction in UKIDSS J band phys.absorption.gal;em.IR.J
A_K mag Galactic extinction in UKIDSS K band phys.absorption.gal;em.IR.K
A_NUV mag Galactic extinction in GALEX NUV band phys.absorption.gal;em.UV.200-300nm
A_Y mag Galactic extinction in UKIDSS Y band phys.absorption.gal;em.IR.NIR
A_g mag Galactic extinction in SDSS g band phys.absorption.gal;em.opt.B
A_i mag Galactic extinction in SDSS i band phys.absorption.gal;em.opt.I
A_r mag Galactic extinction in SDSS r band phys.absorption.gal;em.opt.R
A_u mag Galactic extinction in SDSS u band phys.absorption.gal;em.opt.U
A_z mag Galactic extinction in SDSS z band phys.absorption.gal;em.opt
CATAID - Unique GAMA of object meta.id;meta.main
DEC deg DEC of position for which the extinction was calculated (J2000) pos.eq.dec
EBV mag E(B-V) phys.absorption.gal
RA deg RA of position for which the extinction was calculated (J2000) pos.eq.ra
InputCatA
name: InputCatA | type: table | 2010-05-21 | Ivan Baldry [javascript protected email address] | version v05 |
SDSS DR6 data of GAMA I survey regions. This is GAMA`s master input catalogue.
InputCat
InputCatA
v05
2010-05-21
Ivan Baldry

This table contains the r_petro < 19.8 SDSS DR6 input catalogue covering
an enlarged area (120.0 < RA < 230.0, DEC < 3.0), an r_model < 20.5
catalogue covering the three 12x4 GAMA I regions, and a small addition
of i_model < 20.5 and FIRST radio matches.

960510 rows

The creation of the catalogue is derived from four SQL queries to
casjobs DR6. This is the order in which objects were added to this
catalogue. The GAMA ID called CATAID runs from 0 to 960509 following
the order of these queries.

..................................................................

(689669 rows: original version while GAMA regions were still being
finalised)

select ...
into ... from dr6.PhotoObj as p
where p.psfmag_r - p.modelmag_r > 0.25 and
p.petromag_r - p.extinction_r < 19.8 and
p.petromag_r - p.extinction_r > 6.0 and
p.ra > 120.0 and p.ra < 230.0 and p.dec < 3.0 and
((p.mode = 1) or (p.mode = 2 and p.ra < 139.939 and p.dec < -0.5
and (p.status & dbo.fphotostatus('OK_SCANLINE')) > 0))

Only "primary" objects were included except for some "secondary"
objects along the bottom edge of the equatorial stripe. These really
are primary as there are no overlapping stripes. This was necessary
for the GAMA 9-h region.

..................................................................

(61660 rows: adding in compact objects, only a subset will be
targeted)

...
where p.psfmag_r - p.modelmag_r > 0.05 and p.psfmag_r - p.modelmag_r <= 0.25 and
p.petromag_r - p.extinction_r < 19.8 and
p.petromag_r - p.extinction_r > 6.0 and
p.ra > 120.0 and p.ra < 230.0 and p.dec < 3.0 and
((p.mode = 1) or (p.mode = 2 and p.ra < 139.939 and p.dec < -0.5
and (p.status & dbo.fphotostatus('OK_SCANLINE')) > 0))

..................................................................

(208196 rows: adding in objects to r_model < 20.5 in selected regions)

...
where p.psfmag_r - p.modelmag_r > 0.05 and
p.modelmag_r - p.extinction_r < 20.5 and
p.petromag_r - p.extinction_r >= 19.8 and
( (p.ra > 129.0 and p.ra < 141.0 and p.dec > -1.0 and p.dec < 3.0) or
(p.ra > 174.0 and p.ra < 186.0 and p.dec > -2.0 and p.dec < 2.0) or
(p.ra > 211.5 and p.ra < 223.5 and p.dec > -2.0 and p.dec < 2.0) ) and
((p.mode = 1) or (p.mode = 2 and p.ra < 139.939 and p.dec < -0.5
and (p.status & dbo.fphotostatus('OK_SCANLINE')) > 0))

..................................................................

(985 rows: adding in objects to i_model < 20.5 with FIRST radio match)

...
into ... from dr6.PhotoObj as p join dr6.first as f on f.objid = p.objid
where p.modelmag_i - p.extinction_i < 20.5 and
( p.psfmag_r - p.modelmag_r <= 0.05 or
(p.modelmag_r - p.extinction_r >= 20.5 and
p.petromag_r - p.extinction_r >= 19.8) ) and
( (p.ra > 129.0 and p.ra < 141.0 and p.dec > -1.0 and p.dec < 3.0) or
(p.ra > 174.0 and p.ra < 186.0 and p.dec > -2.0 and p.dec < 2.0) or
(p.ra > 211.5 and p.ra < 223.5 and p.dec > -2.0 and p.dec < 2.0) ) and
((p.mode = 1) or (p.mode = 2 and p.ra < 139.939 and p.dec < -0.5
and (p.status & dbo.fphotostatus('OK_SCANLINE')) > 0))

............................................................................
Address this table as gama_dr2.InputCatA
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - Unique GAMA ID of object meta.id;meta.main
DEC deg J2000 coordinate pos.eq.dec
EXTINCTION_R mag r-band Galactic extinction phys.absorption.gal;em.opt.R
FIBERMAG_R mag 3-arcsec fiber magnitude phot.mag;em.opt.R
FLAGS - See SDSS photoobj table meta.code.qual;phot
FLAGS_R - See SDSS photoobj table meta.code.qual;phot;em.opt.R
MODELMAG_G mag DR6 mag phot.mag;em.opt
MODELMAG_I mag DR6 mag phot.mag;em.opt.I
MODELMAG_R mag DR6 mag phot.mag;em.opt.R
MODELMAG_U mag DR6 mag phot.mag;em.opt.U
MODELMAG_Z mag DR6 mag phot.mag;em.opt
OBJID - SDSS objid meta.id
PETROMAG_G mag DR6 mag phot.mag;em.opt
PETROMAG_I mag DR6 mag phot.mag;em.opt.I
PETROMAG_R mag DR6 mag phot.mag;em.opt.R
PETROMAG_U mag DR6 mag phot.mag;em.opt.U
PETROMAG_Z mag DR6 mag phot.mag;em.opt
PETROR50_R arcsec Radius containing 50% of Petrosian flux phys.angSize;em.opt.R
PETROR90_R arcsec Radius containing 90% of Petrosian flux phys.angSize;em.opt.R
PETRORAD_R arcsec Petrosian radius phys.angSize;em.opt.R
PRIMTARGET - See SDSS photoobj table meta.code.class
PSFMAG_R mag PSF magnitude phot.mag;em.opt.R
RA deg J2000 coordinate pos.eq.ra
RUN - SDSS run number obs.param
STATUS - See SDSS photoobj table meta.code.status
SpStandards
name: SpStandards | type: table | 2011-01-13 | Ivan Baldry [javascript protected email address] | version v06 |
Standard stars from SDSS.
InputCat
SpStandards
v06
2011-01-13
Ivan Baldry

This table contains standard stars from SDSS used in GAMA observing.
The standard stars can be used to tie the AAOmega spectra to SDSS
spectrophotometric calibration, at least in an average sense.

The standards were selected using the flag sectarget=2 or
sectarget=32. The magnitude restrictions were fibermag_r > 16.9 and
16.6 < psfmag_r < 18.4. Magnitudes were not extinction corrected.

priority_class (p):

p=3: SDSS standard stars with SDSS spectra obtained
p=2: classified as SPECTROPHOTO_STD
p=1: classified as REDDEN_STD
p=0: close proximity to science targets

See SDSS EDR paper (Stoughton et al. 2002, sec 4.8.5).

Address this table as gama_dr2.SpStandards
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - GAMA ID meta.id;meta.main
DEC deg J2000 coordinate pos.eq.dec
FIBERMAG_R mag DR7 mag phot.mag;em.opt.R
OBJID - SDSS ID meta.id
PRIORITY_CLASS - See notes meta.code.class
PSFMAG_G mag DR7 mag phot.mag;em.opt
PSFMAG_I mag DR7 mag phot.mag;em.opt.I
PSFMAG_R mag DR7 mag phot.mag;em.opt.R
RA deg J2000 coordinate pos.eq.ra
RUN - SDSS run number obs.param
SECTARGET - 2^1 for REDDEN_STD, 2^5 for SPECTROPHOTO_STD meta.code.class
STATUS - SDSS status flag related to primary secondary meta.code.status
TilingCat
name: TilingCat | type: table | 2011-07-21 | Ivan Baldry [javascript protected email address] | version v16 |
Science targets and information for tiling and spectroscopic observation.
InputCat
TilingCat
v16
2011-07-21
Ivan Baldry

This catalog is used to keep track of the state of the survey. During
survey operations it is updated as soon as new redshifts are available
and it is used to set the priorities for the next observing run. The
present version of this catalog is the final GAMA I version (i.e.
after the completion of all GAMA I observations).

Note that this table contains the complete tiling catalog, not just
the objects for which redshifts are released in DR2 (r < 19.0 in G09
and G12, and r < 19.4 in G15). Objects included in DR2 may be
identified using the column DR2_FLAG. Those objects for which
redshifts are not released in DR2 have their redshift column Z set to
-9.99999. However, the redshift quality column NQ has not been
modified, and so this column informs users whether a good quality
redshift for this object exists (but is not released yet).

This table is derived from InputCatA, selecting GAMA regions (12x4
deg^2; G09, G12, G15), applying magnitude limits, star-galaxy
separation, surface-brightness limits, and mask.

The full details are given in the Input Catalog (IC) paper, Baldry et
al. (2010)
.

The redshifts in this table are obtained from table SpecAll in the
SpecCat DMU by matching by CATAID except for a few cases. There are 5
cases where an object is matched within 1 arcsec to a spectrum that
has been assigned to another object.

In the following we provide some additional information on individual
columns of this table.

...............................................................................

SURVEY_CODE for source of redshift

1=SDSS, 2=2dFGRS, 3=MGC, 4=2SLAQ-LRG, 5=GAMA, 6=6dFGS, 7=UZC, 8=2QZ,
9=2SLAQ-QSO, 10=NED, 11=GAMA_LT, 12=WiggleZ
...............................................................................

TARGET_FLAGS (t) (showing which target criteria are satisfied)
(bitwise set of flags, bit X):

X t=2^X meaning
0 1 SDSS main galaxy sample
1 2 SDSS LRG sample
2 4 r < 19.0 and r_psf-r_model > 0.25 (high priority in Year 1)
3 8 r < 19.4 (G09,G15) or r < 19.8 (G12)
4 16 r < 19.8
5 32 z_model < 18.2
6 64 K_AB < 17.6
7 128 (g_model < 20.6 or r_model < 19.8 or i_model < 19.4) (G12)
8 256 radio_flux > 0.0
...............................................................................

SURVEY_CLASS (sc)

sc = 0: not a target (except for checks on vis_class=3)
sc = 1: target only because of radio selection (F1 not (MS or F2 or F3))
sc >= 2: passes star-galaxy separation criteria (MS, F2 or F3)
sc >= 3: r < 19.8 or zK-selected (MS, F2) (uniform selection in all regions)
sc >= 4: *** MS ***
sc >= 5: MS r or z-selected
sc >= 6: *** MS r-selected only ***
sc >= 7: r < 19.0 and sg_sep > 0.25 (Year 1 high priority targets)

See the IC paper for details on the selection. 'MS' means main survey:
main survey =
(r < 19.4 (G09,G15) or r < 19.8 (G12) or K_AB < 17.6 or z_{model} < 18.2)

For science catalogs: select, for example,
SURVEY_CLASS >= 4 for all main survey targets (see IC paper),
SURVEY_CLASS >= 6 for r-selection only (r < 19.4 in G09 & G15, r < 19.8 in G12)

F1, F2, and F3 are filler selections. These targets are only allocated
a fibre when the fibre cannot be allocated to a MS target.

DR2 only includes data for MS objects, i.e. SURVEY_CLASS >= 4.

Further note: Objects with target_flags=0 (also survey_class=0) have
2<=vis_class<=4 or they are excluded by Eq. 12 only of the IC paper
(Sec. 5.2). These remain in the tiling catalogue because they are rejected by
a more subjective criteria than the other selections.
...............................................................................

MASK_IC_10 / MASK_IC_12:

These parameters encode the bright star mask. The bright star mask is
based on stars in the Tycho 2, Tycho 1 and Hipparcos catalogues. For
each bright star, a scattered-light radius (R_s) was estimated based
on the circular region over which the star flux per pixel is greater
than five times the sky noise level. For each object in TilingCat
MASK_IC_10 is defined as follows:

d <= R_s : MASK_IC_10 = 1
R_s < d <= 5*R_s : MASK_IC_10 = R_s / d
d > 5*R_s : MASK_IC_10 = 0

where d is the distance between the object and the nearest V < 10 mag
star, which has scattered light radius R_s. In other words, the
MASK_IC_10 value decreases from unity when d <= R_s to 0.2 when d =
5*R_s, and then jumps to 0 when d > 5*R_s. MASK_IC_12 is defined in
the same way for V < 12 mag stars. In addition, objects within an SDSS
database mask for holes, satellite trails or bleeding pixels had these
mask values set to unity.
...............................................................................

PRIORITY_CLASS (p):

p > 1 except p=2,4,7 satisfy survey_class >= 3;
p > 1 satisfy fiber mag limits 16.8 < r_fib < 22.8;
p > 1 expect p=7 satisfy vis_class<=1 or vis_class=255.

p=9: Q<=2 and num_gama_spec = 0 (target but never attempted)
p=8: Q<=2 and num_gama_spec = 1 (only one failed GAMA observation)

p=7: Q<=2 and vis_class=3 (would be a target other than vis_class)
p=6: Q=3 and num_gama_spec <=1 (to check the Q=3 redshift blunder rate)

p=5: Q<=2 and num_gama_spec >=2 (two or more failed GAMA observations)
p=4: Q<=2 other targets (sc=1 or sc=2)

p=3: Q=3 and num_gama_spec >=2 or Q >= 4 (sc >= 3 done)
p=2: Q >= 3 other targets (sc=1 or sc=2 done)

p=0: all others including: vis_class=2-4 objects, fibre bright or fibre faint.
...............................................................................

VIS_CLASS for visual classification

0 = not eyeballed
1 = yes a target
2 = not a target (no evidence of galaxy light)
3 = not a target (not the main part of a galaxy)
4 = compromised photometry (selection mag has serious error)
255 = not eyeballed but the following flags are *all* zero
EDGE, BLENDED, CHILD, MAYBE_CR, MAYBE_EGHOST
...............................................................................
Address this table as gama_dr2.TilingCat
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - Unique GAMA ID of object meta.id;meta.main
DEC deg J2000 coordinate pos.eq.dec
DR2_FLAG - Indicates whether spectra, redshifts and ancillary data for this object are released in DR2 meta.code
FIBERMAG_R mag 3-arcsec fiber magnitude phot.mag;em.opt.R
G_MODEL mag Extinction-corrected SDSS DR6 mag phot.mag;em.opt.B
I_MODEL mag Extinction-corrected SDSS DR6 mag phot.mag;em.opt.I
K_AUTO mag Extinction-corrected r-defined auto AB mag phot.mag;em.IR.K
MASK_IC_10 - Mask value 0.0 to 1.0 around V<10 stars meta.code
MASK_IC_12 - Mask value 0.0 to 1.0 around V<12 stars meta.code
NEIGHBOUR_CLASS - Number of priority_class>=8 targets within 40 arcsec meta.code.class
NQ - Quality of redshift meta.code.qual;src.redshift
NUM_GAMA_SPEC - Number of GAMA spectra matched to object meta.number;spect
OBJID - SDSS objid meta.id
PRIORITY_CLASS - Priorities for targeting, see notes meta.code.class
RA deg J2000 coordinate pos.eq.ra
R_MODEL mag Extinction-corrected SDSS DR6 mag phot.mag;em.opt.R
R_PETRO mag Extinction-corrected SDSS DR6 Petrosian mag phot.mag;em.opt.R
R_SB mag/arcsec^2 SDSS Petro half-light surface brightness phot.mag.sb;em.opt.R
SG_SEP mag r_psf - r_model star-galaxy separation parameter src.class.starGalaxy
SG_SEP_JK mag J - K - f_locus star-galaxy separation parameter src.class.starGalaxy
SPECID - ID of spectrum from SpecAll table meta.id.cross;spect
SURVEY_CLASS - Useful for selecting samples, see notes meta.code.class
SURVEY_CODE - Survey code for redshift source, see notes meta.code;meta.dataset
TARGET_FLAGS - Bitwise target criteria, see notes meta.code
U_MODEL mag Extinction-corrected SDSS DR6 mag phot.mag;em.opt.U
VIS_CLASS - Visual classification, see notes mata.code.qual
VIS_CLASS_USER - Initials of classifiers, xxx for none meta.id
Z - Spectroscopic redshift, -1 for none attempted src.redshift
Z_MODEL mag Extinction-corrected SDSS DR6 mag phot.mag;em.opt.I
LocalFlowCorrection
name: LocalFlowCorrection | type: group | 2011-11-22 | Ivan Baldry [javascript protected email address] | version v07 |
This DMU performs local flow correction, and provides redshifts in different frames of reference.
DistancesFrames
name: DistancesFrames | type: table | 2011-11-22 | Ivan Baldry [javascript protected email address] | version v07 |
This table provides redhifts in various reference frames, flow corrected redshifts, and distance moduli for all GAMA DR2 objects.
LocalFlowCorrection
DistancesFrames
v07
2011-11-22
Ivan Baldry

This table provides redshifts in various reference frames, flow
corrected redshifts, and distance moduli for all GAMA DR2 objects with
z > -0.01 and nQ >= 2. Note that only nQ >= 3 redshifts should be
considered reliable.

The implementation of the frame and flow-model redshifts is described
in section 2.3 of Baldry et al. (2012). The effect on the distance
moduli is significant at z < 0.03, see figure 2 of the paper.

The heliocentric redshifts are obtained from the table SpecAll in the
SpecCat DMU.

CMB frame uses the dipole from Lineweaver et al. (1996); and the Local
Group frame uses the conversion from Courteau & van den Bergh (1999).

z_tonry uses the Tonry et al. (2000) flow model described in the
Appendix of that paper. Note there are triple-valued solutions of
z_cmb -> z_tonry over a small range in G12 (near Virgo cluster), here
the average distance is used. The solution is tapered to z_cmb from
z_cmb = 0.02 to z_cmb = 0.03. Thus z_tonry = z_cmb at z_cmb > 0.03.
z_tonry is close to but not exactly equal to z_lg (Local Group frame
redshift) at < ~10 Mpc.

The distance moduli given in the table are determined using z_tonry
only for entries where the velocity (c z_tonry) > 300 km/s (z > 0.001;
D_L > 3 Mpc/h). Note this does not guarantee that stars with large
redshift errors will be excluded. Either the spectra and images need
to be checked or a more restrictive cut should be used. For objects
with z < 0.001, the distance modulus is not calculated and is given
the value zero.

Address this table as gama_dr2.DistancesFrames
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - Unique ID of GAMA object meta.id;meta.main
DEC deg J2000 coordinate pos.eq.dec
DM_100_25_75 mag distance modulus for H0=100, 0.25, 0.75 phot.mag.distMod
DM_100_30_70 mag distance modulus for H0=100, 0.30, 0.70 phot.mag.distMod
DM_70_30_70 mag distance modulus for 737 cosmology phot.mag.distMod
NQ - quality of redshift (use nQ > 2 for science) meta.code.qual;src.redshift
RA deg J2000 coordinate pos.eq.ra
Z_CMB - CMB frame redshift src.redshift
Z_HELIO - heliocentric redshift src.redshift
Z_LG - Local Group frame redshift src.redshift
Z_TONRY - flow corrected redshift using Tonry et al. model src.redshift
Z_TONRY_HIGH - recomputed after adjusting z_helio by +180 km/s src.redshift
Z_TONRY_LOW - recomputed after adjusting z_helio by -180 km/s src.redshift
SersicPhotometry
name: SersicPhotometry | type: group | 2011-10-13 | Lee Kelvin [javascript protected email address] | version v07 |
This DMU provides a single-component Sersic fit in each of the ugrizYJHK bands for every GAMA DR2 galaxy.
SersicPhotometry
2011-10-13
Lee Kelvin

The SersicPhotometry DMU produces a single-Sersic (1-component only)
fit to every GAMA DR2 object in each of the bands ugrizYJHK. This is
achieved by using SIGMA v0.9-0 (Structural Investigation of Galaxies
via Model Analysis) on SDSS and UKIDSS LAS imaging data. SIGMA is a
wrapper around several contemporary astronomy tools such as Source
Extractor (Bertin & Arnouts 1996), PSF Extractor (Bertin and Delorme,
priv. comm.) and GALFIT 3 (Peng et al. 2010), as well as analysis and
processing code writting in the open-source R programming language (R
Development Core Team, 2010). Please cite Kelvin et al. (2012) when
using data products from this DMU.

GALFIT is the workhorse fitting algorithm used within SIGMA. To
produce a model of a galaxy, GALFIT must be provided with suitable
starting parameters (such as size, magnitude, ellipticity, etc), an
appropriate PSF and cutouts of both the science data and any
associated weight maps. The cutouts are created from the GAMA v02
mosaics (available on the DR2 file server, swpim* files), with
physical initial conditions and the PSF provided by Source Extractor
and PSF Extractor, respectively. These programs are called and setup
automatically within the SIGMA script, their outputs reprocessed into
a form GALFIT is able to read, and fed into GALFIT. GALFIT uses a
simple downhill minimisation in order to minimise the global-chi^2 of
the model. Its outputs are analysed by SIGMA for any obvious errors,
and if found, an attempt at fixing them will automatically be made.

This DMU provides two tables: SersicCatAll and SersicCat. The former
contains a complete record of all of the outputs produced by
SIGMA. The latter table only contains those columns considered to be
most useful to the users. In other words, SersicCat contains an exact
subset of the columns in SersicCatAll.

Below are more detailed notes on several of the columns provided by
the SersicPhotometry DMU. The unique identifier for the
SersicPhotometry DMU is the CATAID (column 1) which refers to the GAMA
ID of an object. Null entries in SersicCat are labelled -9999. For
further details on the operation of SIGMA, please refer to Kelvin et
al. (2012).

##############################################################################

Dependencies:
InputCat TilingCat
Mosaics v02

##############################################################################

Potential zero-point offsets

Please see the notes of the table ApMatchedCat.

##############################################################################

SIGMA_INDEX

A unique identifier that the SIGMA code uses to identify each
galaxy. This remains a part of SIGMA for historical reasons.

##############################################################################

OBJNAME

SIGMA_INDEX, padded with leading zeroes to make the total length 8
characters long, and then prefixed with an S to construct the OBJNAME.
This name is more commonly used when saving modelling data within the
GAMA database.

##############################################################################

URL

Location of the directory on the file server containing all of the
input and output files used and produced by SIGMA for this galaxy. For
more details on the contents of this directory see the directory
description on the file server.

Please note that the world coordinate system (WCS) information in the
headers of the various fits files found in this directory is partially
incorrect. The pixel sizes are correct, but the absolute positions
implied by the WCS information in the header are incorrect.

##############################################################################

PSF_

All columns starting with 'PSF_' are outputs of the PSF Extractor
pipeline within SIGMA. These outputs are provided for reference only
to aid in the understanding of the final single-Sersic model. For more
information, see Kelvin et al. (2012).

##############################################################################

SEX_

All columns starting with 'SEX_' are outputs of the Source Extractor
pipeline within SIGMA. These Source Extractor outputs provided the
starting parameters for the GALFIT inputs used during minimisation.
These outputs are provided *for reference only* to aid in the
understanding of the final single-Sersic model. Unless there is a very
good reason to do so, these should not be used in scientific analyses.
Their GAL_ equivalents (see below) should be used instead. For more
information, see Kelvin et al. (2012).

##############################################################################

GAL_

All columns starting with 'GAL_' are final outputs of the GALFIT
pipeline within SIGMA. These GALFIT outputs provide the main output of
the SersicPhotometry DMU. For more information, see Kelvin et al. (2012).

##############################################################################

SEX_PA/GAL_PA

The position angle on the image recovered from Source Extractor and
GALFIT, respectively. This is defined from the positive x-axis of the
image (roughly aligned to west), increasing from zero anti-clockwise.

NOTE: SEX_PA goes from -90 to +90, whereas GAL_PA goes from 0 to +180,
however the definitions below still hold true at all times.

x-positive 0 degrees
y-positive 90 degrees
x-negative 180 degrees (equivalent to x-positive, redundant)
y-negative -90 degrees (equivalent to y-positive, redundant)

Unfortunately, due to an oversight, this DMU does *not* include
equivalent angles on the sky. However, an approximate on-sky angle can
be recovered as

SEX_PA_J2000_X = SEX_PA_X + (THETA_J2000 - THETA_IMAGE)
GAL_PA_J2000_X = GAL_PA_X + (THETA_J2000 - THETA_IMAGE)

where THETA_J2000 and THETA_IMAGE are the on-sky and on-image position
angles, respectively, listed in the table ApMatchedCat in the
ApMatchedPhotom DMU.

Despite this being only an approximation we recommend the use of
GAL_PA_J2000_X over THETA_J2000.

Note that SEX_PA_R in this DMU and THETA_IMAGE in the ApMatchedPhotom
DMU are not identical due to the procedures employed by these DMUs
being slightly different.

##############################################################################

GAL_FIT

The function combination chosen to model. Since the SersicPhotometry
is tasked with fitting a single-Sersic component to every galaxy, this
value will always be either 1 or -9999 (null). GAL_FITWORD gives the
corresponding word describing the combination chosen to model instead
of a number.

1 Sersic
2 Sersic + Exponential
3 Sersic + Sersic disk
4 Sersic bulge + Sersic disk (bulge/disk Re < 1, bulge/disk n > 1)
5 de Vaucouleurs + Exponential
-9999 Null

##############################################################################

GAL_RESULT

The end result of the GALFIT fitting stage.

CRASH An error has occurred causing the code to crash, usually due to bad
inputs caused by nearby star contamination or bad data.

ERROR A fatal error has occurred within GALFIT causing the code to
quit before minimisation. Usually caused by extremely bad inputs from
Source Extractor, or a bad PSF.

OKAY GALFIT completed successfully and SIGMA was happy enough with its
outputs to move on to the next galaxy in the catalogue. A flag
of OKAY does not mean that the result is perfect, i.e. physically
meaningful, it merely reflects that GALFIT was able to finish
without a major error occurring.

##############################################################################

GAL_QFLAG

This is a binary flag, and describes the quality of the final fit.
Flags may add together to produce a number higher than 1024.

0 fine
1 no object detected
2 compromised photometry (an object brighter than 0.75 mags fainter than
the primary lies within 4re)
4 magnitude between SEx and GALFIT differs by +-1 mag
8 crash/error
16 center migrated (> 5 pixels)
32 max. iterations (100)
64 large radius (ln[RAD/FLUXRAD]>2)
128 small radius (ln[RAD/FLUXRAD]<-2)
256 high Sersic index (n>10)
512 high ellipticity (e>0.95)
1024 bad chi2 (chi2<0.5 or chi2>2)

##############################################################################

GAL_GHFLAG

This is a binary flag, and describes the global fitting history
(i.e. non-Sersic specific).

Flags may add together to produce a number higher than 4. Multiple
runs cause the GHFLAG value to loop over and start at the next logical
binary operator (1,2,4,8,16,32...), and so many fitting runs can cause
GHFLAG to get very large. Example: the first run has a bad chi2 and
reached its maximum iterations, whereas the second run only had a bad
chi2. This would give 4+2 from run 1, and 32 from run 2, giving a
total GHFLAG of 38.

0 fine
1 crash/error
2 max iterations (100)
4 bad chi2 (chi2<0.5 or chi2>2)

##############################################################################

GAL_CHFLAG

This is a binary flag, and describes the component fitting history
(i.e. Ssersic specific).

Flags may add together to produce a number higher than 16. Multiple
runs cause the CHFLAG value to loop over and start at the next logical
binary operator (1,2,4,8,16,32...), and so many fitting runs can cause
CHFLAG to get very large. Example: the first run has a high
ellipticity and a high Sersic index, and the second run has a large
radius. This would give 16+8 from run 1, and 64 from run 2, giving a
total CHFLAG of 88.

0 fine
1 center migrated (> SEx re)
2 large radius (ln[RAD/FLUXRAD]>3)
4 small radius (ln[RAD/FLUXRAD]<-3)
8 high Sersic index (n>10)
16 high ellipticity (e>0.95)

##############################################################################

GAL_TYPE

GALFIT output type. Since the SersicPhotometry DMU is tasked with
fitting a single-Sersic component to every galaxy, this value will
always be either 1, 2, 5 or -9999 (null). GAL_TYPEWORD gives the
corresponding word describing the output type instead of a number.

1 crash
2 error
3 sky
4 psf
5 sersic
6 expdisk
7 edgedisk
8 ferrer
9 nuker
-9999 Null

##############################################################################

_MAG_

Magnitudes presented in this catalogue have not been corrected for the
effect of foreground Milky Way dust extinction. Should these
corrections be required, they can be obtained from the table
GalacticExtinction in the InputCat DMU.

All photometry is on the AB system.

##############################################################################

SersicCat
name: SersicCat | type: table | 2011-10-13 | Lee Kelvin [javascript protected email address] | version v07 |
This catalogue contains the most useful subset of the output of the SersicPhotometry DMU, using SIGMA v0.9-0 (Structural Investigation of Galaxies via Model Analysis) to generate a single-Sersic fit to every GAMA DR2 object. This table is an exact subset of the table SersicCatAll.
Address this table as gama_dr2.SersicCat
Name Unit Description UCD (hover for description)
Name Unit Description UCD
CATAID - GAMA Object ID meta.id
DEC deg Declination (J2000) pos.eq.dec
FILENAME - Full path to object`s data directory meta.id;meta.file
GAL_CHI2_G - reduced Chi^2 of output model stat.fit.goodness;em.opt
GAL_CHI2_H - reduced Chi^2 of output model stat.fit.goodness;em.IR.H
GAL_CHI2_I - reduced Chi^2 of output model stat.fit.goodness;em.opt.I
GAL_CHI2_J - reduced Chi^2 of output model stat.fit.goodness;em.IR.J
GAL_CHI2_K - reduced Chi^2 of output model stat.fit.goodness;em.IR.K
GAL_CHI2_R - reduced Chi^2 of output model stat.fit.goodness;em.opt.R
GAL_CHI2_U - reduced Chi^2 of output model stat.fit.goodness;em.opt.U
GAL_CHI2_Y - reduced Chi^2 of output model stat.fit.goodness;em.IR.NIR
GAL_CHI2_Z - reduced Chi^2 of output model stat.fit.goodness;em.opt
GAL_DEC_G deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.opt
GAL_DEC_H deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.IR.H
GAL_DEC_I deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.opt.I
GAL_DEC_J deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.IR.J
GAL_DEC_K deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.IR.K
GAL_DEC_R deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.opt.R
GAL_DEC_U deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.opt.U
GAL_DEC_Y deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.IR.NIR
GAL_DEC_Z deg Declination as determined by GALFIT pos.eq.dec;meta.modelled;em.opt
GAL_ELLIP_G - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.opt
GAL_ELLIP_H - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.IR.H
GAL_ELLIP_I - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.opt.I
GAL_ELLIP_J - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.IR.J
GAL_ELLIP_K - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.IR.K
GAL_ELLIP_R - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.opt.R
GAL_ELLIP_U - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.opt.U
GAL_ELLIP_Y - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.IR.NIR
GAL_ELLIP_Z - ellipticity (1-(b/a)) src.ellipticity;meta.modelled;em.opt
GAL_INDEX_G - Sersic index stat.fit.param;meta.modelled;em.opt
GAL_INDEX_H - Sersic index stat.fit.param;meta.modelled;em.IR.H
GAL_INDEX_I - Sersic index stat.fit.param;meta.modelled;em.opt.I
GAL_INDEX_J - Sersic index stat.fit.param;meta.modelled;em.IR.J
GAL_INDEX_K - Sersic index stat.fit.param;meta.modelled;em.IR.K
GAL_INDEX_R - Sersic index stat.fit.param;meta.modelled;em.opt.R
GAL_INDEX_U - Sersic index stat.fit.param;meta.modelled;em.opt.U
GAL_INDEX_Y - Sersic index stat.fit.param;meta.modelled;em.IR.NIR
GAL_INDEX_Z - Sersic index stat.fit.param;meta.modelled;em.opt
GAL_MAG_10RE_G mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.opt
GAL_MAG_10RE_H mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.IR.H
GAL_MAG_10RE_I mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.opt.I
GAL_MAG_10RE_J mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.IR.J
GAL_MAG_10RE_K mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.IR.K
GAL_MAG_10RE_R mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.opt.R
GAL_MAG_10RE_U mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.opt.U
GAL_MAG_10RE_Y mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.IR.NIR
GAL_MAG_10RE_Z mag magnitude of model, truncated at 10*re phot.mag;meta.modelled;em.opt
GAL_MAG_G mag magnitude of Sersic model phot.mag;meta.modelled;em.opt
GAL_MAG_H mag magnitude of Sersic model phot.mag;meta.modelled;em.IR.H
GAL_MAG_I mag magnitude of Sersic model phot.mag;meta.modelled;em.opt.I
GAL_MAG_J mag magnitude of Sersic model phot.mag;meta.modelled;em.IR.J
GAL_MAG_K mag magnitude of Sersic model phot.mag;meta.modelled;em.IR.K
GAL_MAG_R mag magnitude of Sersic model phot.mag;meta.modelled;em.opt.R
GAL_MAG_U mag magnitude of Sersic model phot.mag;meta.modelled;em.opt.U
GAL_MAG_Y mag magnitude of Sersic model phot.mag;meta.modelled;em.IR.NIR
GAL_MAG_Z mag magnitude of Sersic model phot.mag;meta.modelled;em.opt
GAL_MU_0_G mag/arcsec^2 central surface brightness