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Schema Browser

Find detailed descriptions of the data available in each data release

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).

2dFGRS 
name: 2dfgrs | type: Survey | Matthew Colless [javascript protected email address] | website | docs |

The 2dF Galaxy Redshift Survey (2dFGRS) is a major spectroscopic survey taking full advantage of the unique capabilities of the 2dF facility built by the Anglo-Australian Observatory. The 2dFGRS is integrated with the 2dF QSO survey (Croom et al., 2004). The 2dFGRS obtained spectra for 245591 objects, mainly galaxies, brighter than a nominal extinction-corrected magnitude limit of bJ=19.45. Reliable (quality>=3) redshifts were obtained for 221414 galaxies. The galaxies cover an area of approximately 1500 square degrees selected from the extended APM Galaxy Survey in three regions: a North Galactic Pole (NGP) strip, a South Galactic Pole (SGP) strip, and random fields scattered around the SGP strip. Redshifts are measured from spectra covering 3600-8000 Angstroms at a two-pixel resolution of 9.0 Angstrom and a median S/N of 13 per pixel. All redshift identifications are visually checked and assigned a quality parameter Q in the range 1-5; Q>=3 redshifts are 98.4% reliable and have an rms uncertainty of 85 km/s. The overall redshift completeness for Q>=3 redshifts is 91.8% but this varies with magnitude from 99% for the brightest galaxies to 90% for objects at the survey limit (Colless et al., 2007).

Final Data Release
name: fdr | type: DataRelease | ingested: 22 Jun 2020, 11:53 a.m. | Matthew Colless [javascript protected email address] | version 1.0 |
Description is not available for Final Data Release.
Definitive
name: Definitive | type: CatalogueGroup | Matthew Colless [javascript protected email address] | version 1 |
All the available information
spec_all
name: spec_all | type: CatalogueTable | Matthew Colless [javascript protected email address] | version 1 |
All the spectroscopic information
Address this table as 2dfgrs_fdr.spec_all
Name Unit Description UCD (hover for description)
Name Unit Description UCD
best None In extension 0, extension number with best spectrum; in extension>0, 1 if best spectrum and 0 otherwise meta.code
IALTER None No idea meta.cryptic
OBSDECJ2000 deg Observed Dec (J2000) pos.eq.dec
Q_Z_ABS None Cross-correlation quality meta.code.qual
Q_FINAL None Suggested quality for redshift meta.code.qual
OBSRAJ2000 deg Observed RA (J2000) pos.eq.ra
REFRUN None AAT Run number of reference frame obs.param
REFEXP s Exposure time (secs) of reference run obs.exposure
OBJXERR pixels 2dF object x position error stat.error;pos.cartesian.x
OBJYERR pixels 2dF object y position error stat.error;pos.cartesian.y
OBJMAG mag 2dF object magnitude phot.mag
THETA deg 2dF fibre angle instr.param
SNR None Median signal-to-noise ratio per pixel stat.snr;stat.median
PTRTYPE None 2dF ptrtype meta.code
PID None 2dF pid meta.code
OBSFLD None 2dF observed field number obs.field
NCOMB None Number of frames combined meta.number
serial None 2dFGRS serial number meta.id
name None 2dFGRS name meta.id;meta.main
UKST None UKST sky survey field number obs.field
obsrun None Observing run year and month obs.param;obs
TDFgg None 2dFGRS field number (+NGP,-SGP) obs.field
pivot None 2dF pivot obs.param
z None Observed redshift src.redshift
z_helio None Heliocentric redshift src.redshift;pos.heliocentric
abemma None Redshift type (abs=1,emi=2,man=3) meta.code;src.redshift
quality None Redshift quality parameter (quality=1-5; reliable redshifts have quality>=3) meta.code.qual;src.redshift
plate None 2dF plate obs.param
fiber None 2dF fiber obs.param
spectra None Number of spectra for this object meta.number
extnum None Extension number meta.code
OBSNAME None Observed object name meta.id
OBSRA radians Observed RA pos.eq.ra
PIVOT None 2dF pivot number obs.param
FIBRE None 2dF fibre number obs.param
Q_Z_EMI None Emission redshift quality meta.code.qual;src.redshift
Z_HELIO None Heliocentric corrected redshift src.redshift;pos.heliocentric
QUALITY None Redshift measurement quality meta.code.qual;src.redshift
ABEMMA None Redshift type (abs=1, emi=2, man=3) meta.code;src.redshift
KBESTR None Cross-correlation template from best spectrum stat.fit.param
R_CRCOR None Cross-correlation peak stat.fit.param
Z_ABS None Cross-correlation redshift stat.fit.param
Z_COMM None Observers Comment meta.note
THPUT None Fibre Throughput instr.param
GRATANGL deg 2dF grating angle instr.param
LAMBDAC Angstrom Central wavelength em.wl.central
OBJX pixels 2dF object x position pos.cartesian.x
NMBEST None Number of emission lines for Z_EMI meta.number
NGOOD None Number of good emmision lines meta.number
Z_EMI None Emission redshift src.redshift;pos.heliocentric
SPFILE None 2dF reduced data file meta.file
PLATE None 2dF plate number (0 or 1); -99 if none obs.param
UTDATE YYYY:MM:DD UT date of observation time.epoch;obs
SPECTID None 2dF spectrograph ID meta.id;instr
GRATID None 2dF grating ID meta.id;instr
GRATLPMM None 2dF grating line per mm instr.param
GRATBLAZ None 2dF grating blaze direction instr.param
OBSDEC radians Observed Dec pos.eq.dec
MATCH_DR arcsec Position match dr in arcsec pos.angDistance
Z None Raw measured redshift src.redshift
OBSRUN None Observation run obs.param;obs
GRS_DATE None 2dF YYMMDD observed date; -99 if none time.epoch
OBJY pixels 2dF object y position pos.cartesian.y
phot_all
name: phot_all | type: CatalogueTable | Matthew Colless [javascript protected email address] | version 1 |
All the photometric information
Address this table as 2dfgrs_fdr.phot_all
Name Unit Description UCD (hover for description)
Name Unit Description UCD
dec dd mm ss.ss DEC (B1950) in DD MM SS.S pos.eq.dec
best None In extension 0, extension number with best spectrum; in extension>0, 1 if best spectrum and 0 otherwise meta.code
BJSEL mag Final bj mag used in the object selection phot.mag;em.opt.B
PARK None k classification parameter src.morph.param
PROB None psi classification parameter src.morph.param
BJG_OLD mag Original bj magnitude without extinction correction phot.mag;em.opt.B
BJSEL100 mag bj mag used in the object selection (100k) phot.mag;em.opt.B
BJG_100 mag bj without extinction correction (100k) phot.mag;em.opt.B
SBAPM None APM-Supercosmos Bj-band match classification meta.code
SEQNUM None Sequence number: Database Primary Key meta.id
SRSIGMA None Profile classification statistic stat.value
SRBLEND None Deblending flag meta.code
SRQUAL None Quality flag meta.code.qual
SRSB None Supercosmos R vrs Bj match classification meta.code
SRRMAG mag UK-J (R) magnitude phot.mag;em.opt.R
delta radians Dec. (B1950) in radians pos.eq.dec
SRAREA pixels Total area phys.area
SRAI 0.01 microns Weighted semi-major axis phys.angSize.smajAxis
SRBI 0.01 microns Weighted semi-minor axis phys.angSize.sminAxis
SRPA deg Celestial position angle pos.posAng
SRCLASS None Classification flag meta.code
l2 deg Galactic longitude pos.galactic.lon
alpha radians R.A. (B1950) in radians pos.eq.ra
name None 2dFGRS name meta.id;meta.main
ra hh mm ss.ss RA (B1950) in HH MM SS.SS pos.eq.ra
serial None 2dFGRS serial number meta.id
SBBI 0.01 microns Weighted semi-minor axis phys.angSize.sminAxis
DEC radians Dec in radians pos.eq.dec
APMEQNX None Equinox of RA and Dec time.equinox
AREA pixels Isophotal area in pixels phys.area
BJG mag Final bj magnitude without extinction correction phot.mag;em.opt.B
IFIELD None UKST field obs.field
GALEXT mag Galactic extinction phys.absorption
VISCHECK None Visual check flag meta.code
VISCOMM None Visual check comments meta.note
SBPA deg Celestial position angle pos.posAng
SBCLASS None Classification flag meta.code
ra2000 hh mm ss.ss RA (J2000) in HH MM SS.SS pos.eq.ra;meta.main
dec2000 dd mm ss.ss DEC (J2000) in DD MM SS.S pos.eq.dec;meta.main
PARMU None mu classification parameter src.morph.param
JON None Eyeball class flag src.class
ORIENT deg Orientation in degrees clockwise from E-W pos.posAng
REGION None GSSS Region name obs.field
OBJEQNX None Equinox of the plate reference frame time.equinox
OBJRA radians RA in radians pos.eq.ra
OBJDEC radians Dec in radians pos.eq.dec
SBRA deg Object RA (J2000.0) pos.eq.ra
SBDEC deg Object declination (J2000.0) pos.eq.dec
SBBJMAG mag UK-J (Bj) magnitude phot.mag;em.opt.B
SBAREA pixels Total area phys.area
SBAI 0.01 microns Weighted semi-major axis phys.angSize.smajAxis
SBSIGMA None Profile classification statistic stat.value
SBBLEND None Deblending flag meta.code
SBQUAL None Quality flag meta.code.qual
UKST None UKST sky survey field number obs.field
spectra None Number of spectra for this object meta.number
extnum None Extension number meta.code
SRRA deg Object RA (J2000.0) pos.eq.ra
NAME None 2dFgg assigned name meta.id
RA radians RA in radians pos.eq.ra
ECCENT None Eccentricity src.morph.param
BJSELOLD mag Original bj magnitude with extinction correction used in the object selection phot.mag;em.opt.B
SRDEC deg Object declination (J2000.0) pos.eq.dec
b2 deg Galactic latitude pos.galactic.lat
IGAL None Final class flag (equals 1 for a galaxy) src.class.starGalaxy
Key
name: Key | type: CatalogueGroup | Matthew Colless [javascript protected email address] | version 1 |
A subset of astrophysically-important information
spec_key
name: spec_key | type: CatalogueTable | Matthew Colless [javascript protected email address] | version 1 |
Key spectroscopic information for each observation
Address this table as 2dfgrs_fdr.spec_key
Name Unit Description UCD (hover for description)
Name Unit Description UCD
ABEMMA None Redshift type (abs=1, emi=2, man=3) meta.code;src.redshift
Z_EMI None Emission redshift src.redshift;pos.heliocentric
serial None Database serial number (=SEQNUM) meta.id
name None 2dFGRS name (=NAME) meta.id;meta.main
UTDATE YYYY:MM:DD UT date of observation time.epoch;obs
ETA_TYPE None Eta spectral type parameter (-99.9 if none) stat.fit.param
OBSRUN None Observation run obs.param;obs
Z None Redshift (observed) src.redshift
QUALITY None Redshift quality parameter meta.code.qual;src.redshift
Z_ABS None Cross-correlation redshift stat.fit.param
KBESTR None Cross-correlation template stat.fit.param
R_CRCOR None Cross-correlation R value stat.fit.param
NMBEST None Number of emission lines for Z_EMI meta.number
SNR None Median S/N per pixel stat.snr;stat.median
Z_HELIO None Redshift (heliocentric) src.redshift;pos.heliocentric
spec_best
name: spec_best | type: CatalogueTable | Matthew Colless [javascript protected email address] | version 1 |
The best spectrum of each surveyed galaxy
Address this table as 2dfgrs_fdr.spec_best
Name Unit Description UCD (hover for description)
Name Unit Description UCD
ra2000 hh mm ss.ss R.A. (J2000) pos.eq.ra;meta.main
dec2000 dd mm ss.ss Dec. (J2000) pos.eq.dec;meta.main
BJSEL mag Final bj magnitude with extinction correction phot.mag;em.opt.B
BJG_OLD mag Original bj magnitude without extinction correction phot.mag;em.opt.B
SB_BJ mag SuperCosmos bj magnitude without extinction correction phot.mag;em.opt.B
SR_R mag SuperCosmos R magnitude without extinction correction phot.mag;em.opt.R
z None Best redshift (observed) src.redshift
serial None Database serial number (=SEQNUM) meta.id
spectra None Number of spectra obtained meta.number
BJSELOLD mag Original bj magnitude with extinction correction phot.mag;em.opt.B
GALEXT mag Galactic extinction value phys.absorption
name None 2dFGRS name (=NAME) meta.id;meta.main
UKST None UKST plate (=IFIELD) obs.field
ra hh mm ss.ss R.A. (B1950) pos.eq.ra
dec dd mm ss.ss Dec. (B1950) pos.eq.dec
z_helio None Best redshift (heliocentric) src.redshift;pos.heliocentric
BJG mag Final bj magnitude without extinction correction phot.mag;em.opt.B
KBESTR None Cross-correlation template from best spectrum stat.fit.param
R_CRCOR None Cross-correlation R value from best spectrum stat.fit.param
Z_EMI None Emission redshift from best spectrum src.redshift;pos.heliocentric
NMBEST None Number of emission lines for Z_EMI from best spectrum meta.number
SNR None Median S/N per pixel from best spectrum stat.snr;stat.median
ETA_TYPE None Eta spectral type parameter from best spectrum (-99.9 if none) stat.fit.param
obsrun None Observation run of best spectrum obs.param;obs
quality None Redshift quality parameter for best spectrum (quality=1-5; reliable redshifts have quality>=3) meta.code.qual;src.redshift
abemma None Redshift type (abs=1, emi=2, man=3) meta.code;src.redshift
Z_ABS None Cross-correlation redshift from best spectrum stat.fit.param
phot_key
name: phot_key | type: CatalogueTable | Matthew Colless [javascript protected email address] | version 1 |
Key photometric information
Address this table as 2dfgrs_fdr.phot_key
Name Unit Description UCD (hover for description)
Name Unit Description UCD
NAME None 2dFGRS assigned name; if either (i) BJSELOLD is fainter than 19.45, or (ii) the object could not be allocated to a fibre by the configuration algorithm, then NAME is blank meta.id
BJG mag Final bj magnitude without extinction correction phot.mag;em.opt.B
Y_BJ None Plate y_bj in 8 micron pixels instr.scale
DX None Distortion corrected difference (x_bj - x_R)*100 arith.diff
DY None Distortion corrected difference (y_bj - y_R)*100 arith.diff
RMAG mag Unmatched APM 'total' mag phot.mag
BJSELOLD mag Original bj magnitude with extinction correction (prior to re-calibration to BJSEL); used to select survey sample phot.mag;em.opt.B
100_BJG mag 100k release bj magnitude without extinction correction (prior to re-calibration to BJG) phot.mag;em.opt.B
100BJSEL mag 100k release bj magnitude with extinction correction (prior to re-calibration to BJSEL) phot.mag;em.opt.B
SEQNUM None Assigned sequence number to this object; determines the filename (SEQNUM.fits) meta.id
ra hh mm ss.ss R.A. (B1950) in HH MM SS.SS pos.eq.ra
dec dd mm ss.ss Dec. (B1950) in DD MM SS.S pos.eq.dec
PARK None k classification parameter = k / k_star src.morph.param
AREA pixels Isophotal area in pixels phys.area
PARMU None mu classification parameter = mu / mu_star src.morph.param
PMAG mag Unmatched raw APM profile integrated mag phot.mag
FMAG mag Unmatched raw APM 2" profile integrated mag phot.mag
SMAG mag Unmatched raw stellar mag (from APMCAL) phot.mag
REDMAG mag Not used phot.mag;em.opt.R
IFIELD None UKST field obs.field
IGFIELD None Galaxy number in UKST field meta.number
X_BJ None Plate x_bj in 8 micron pixels instr.scale
PROB None psi classification parameter: for eyeballed galaxies, psi*1000 = (10000 + abs(jon) + psi*100); for eyeballed non-galaxies, psi*1000 = -(10000 + abs(jon) + psi*100) src.morph.param
ORIENT deg Orientation measured in degrees clockwise from E to W: orient = 180/pi * atan(2*sxy/((sxx + syy)*(1 + e)-syy)) pos.posAng
ECCENT None Eccentricity (e): e*200 = 200*(((sxx-syy)**2 + 4sxy**2)**0.5)/(sxx + syy) src.morph.param
JON None Eyeball classification, value > 0 only for galaxies brighter than about 18th mag: 0 = noise, 1 = S0, 2 = elliptical, 3 = spiral, 4 = irregular, 5 = undetermined galaxy, 6 = star, 7 = star + star merger, 8 = galaxy + star merger, 9 = galaxy + galaxy merger src.class
BJG_OLD mag Original bj magnitude without extinction correction (prior to re-calibration to BJG) phot.mag;em.opt.B
BJSEL mag Final bj magnitude with extinction correction (i.e. with corrections for isophote, field-effects and plate-matching, then calibrated to total mags with saturation correction, and then extinction corrected) phot.mag;em.opt.B
IGAL None Final classification: -4 = noise, -3 = star + star, -2 = star + fuzz, -1 = star, 0 = galaxy + star merger, 1 = galaxy, 2 = galaxy + galaxy merger src.class.starGalaxy
spec_sum
name: spec_sum | type: CatalogueTable | Matthew Colless [javascript protected email address] | version 1 |
Summary of spectroscopic information
Address this table as 2dfgrs_fdr.spec_sum
Name Unit Description UCD (hover for description)
Name Unit Description UCD
ra2000 hh mm ss.ss R.A. (J2000) pos.eq.ra;meta.main
BJSEL mag Final bj magnitude with extinction correction phot.mag;em.opt.B
BJG_OLD mag Original bj magnitude without extinction correction phot.mag;em.opt.B
BJSELOLD mag Original bj magnitude with extinction correction phot.mag;em.opt.B
GALEXT mag Galactic extinction value phys.absorption
SB_BJ mag Supercosmos bj magnitude without extinction correction phot.mag;em.opt.B
SR_R mag Supercosmos R magnitude without extinction correction phot.mag;em.opt.R
best None FITS extension number of the best spectrum meta.code
z None Best redshift (observed) src.redshift
z_helio None Best redshift (heliocentric) src.redshift;pos.heliocentric
obsrun None Observation run of best spectrum obs.param;obs
quality None Redshift quality parameter (quality=1-5; reliable redshifts have quality>=3) meta.code.qual;src.redshift
serial None Database serial number (=SEQNUM) meta.id
spectra None Number of spectra meta.number
name None 2dFGRS name (=NAME) meta.id;meta.main
UKST None UKST plate (=IFIELD) obs.field
ra hh mm ss.ss R.A. (B1950) pos.eq.ra
dec dd mm ss.ss Dec. (B1950) pos.eq.dec
dec2000 dd mm ss.ss Dec. (J2000) pos.eq.dec;meta.main
BJG mag Final bj magnitude without extinction correction phot.mag;em.opt.B
AAT
name: AAT | type: SpectraFacility |
All 2dFGRS spectra taken with the AAT.
1D Spectrum
name: spectrum_1d | type: SpectrumDataProduct | version v1.0 |
Reduced 1D spectrum
GAMA 
name: gama | type: Survey | Simon Driver [javascript protected email address] | website | docs |

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: DataRelease | ingested: 22 Jun 2020, 11:53 a.m. | Simon Driver [javascript protected email address] | version 1.0 |
Description is not available for Panchromatic Data Release.
GALEX
name: GALEXGALEXMIS | type: ImagingFacility |
Description is not available for GALEX.
FUV
name: FUV | type: ImagingBand |
Description is not available for FUV.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g09 135.1248 0.2502 icrs j2000 View
g15 217.3748 0.2502 icrs j2000 View
g23 344.9998 -32.4998 icrs j2000 View
g12 179.8748 -0.2498 icrs j2000 View
NUV
name: NUV | type: ImagingBand |
Description is not available for NUV.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g23 344.9998 -32.4998 icrs j2000 View
g12 179.8748 -0.2498 icrs j2000 View
g15 217.3748 0.2502 icrs j2000 View
g09 135.1248 0.2502 icrs j2000 View
Herschel
name: HerschelHATLAS | type: ImagingFacility |
Description is not available for Herschel.
S500
name: S500 | type: ImagingBand |
Description is not available for S500.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g23 344.9980 -32.4983 icrs j2000 View
g15 217.3733 0.2517 icrs j2000 View
g12 179.8733 -0.2483 icrs j2000 View
g09 135.1233 0.2517 icrs j2000 View
P100
name: P100 | type: ImagingBand |
Description is not available for P100.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g23 344.9995 -32.4996 icrs j2000 View
g15 217.3746 0.2504 icrs j2000 View
g09 135.1246 0.2504 icrs j2000 View
g12 179.8746 -0.2496 icrs j2000 View
P160
name: P160 | type: ImagingBand |
Description is not available for P160.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g23 344.9993 -32.4994 icrs j2000 View
g09 135.1244 0.2506 icrs j2000 View
g15 217.3744 0.2506 icrs j2000 View
g12 179.8744 -0.2494 icrs j2000 View
S250
name: S250 | type: ImagingBand |
Description is not available for S250.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g23 344.9990 -32.4992 icrs j2000 View
g15 217.3742 0.2508 icrs j2000 View
g09 135.1242 0.2508 icrs j2000 View
g12 179.8742 -0.2492 icrs j2000 View
S350
name: S350 | type: ImagingBand |
Description is not available for S350.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g09 135.1239 0.2511 icrs j2000 View
g12 179.8739 -0.2489 icrs j2000 View
g15 217.3739 0.2511 icrs j2000 View
g23 344.9987 -32.4989 icrs j2000 View
SDSS
name: SDSS | type: ImagingFacility |
Description is not available for SDSS.
i
name: i | type: ImagingBand |
Description is not available for i.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g09 135.1250 0.2500 icrs j2000 View
g12 179.8750 -0.2500 icrs j2000 View
g15 217.3750 0.2500 icrs j2000 View
z
name: z | type: ImagingBand |
Description is not available for z.
Name Approx Central RA Approx Central Dec Frame Equinox Fits Header
g09 135.1250 0.2500 icrs j2000 View
g15 217.3750 0.2500 icrs j2000 View
g12 179.8750 -0.2500 icrs j2000 View