TABLE  grs_ngpSource

Contains the parameters provided for each source in the 2dFGRS NGP photometric catalogue.

The photometric catalogue has been derived from APM scans of the Southern
Sky Survey (see Colless et al. 2001). It's highly complete down to its
nominal limit at an extinction-corrected magnitude (BJSEL) of
approximately bJ=19.45; this limit varies slightly from field to field.

Required constraints:
  • Primary key is (seqNum)

NameTypeLengthUnitDescriptionDefault ValueUnified Content Descriptor
SEQNUMint4 Assigned sequence number to this object; determines the FITS filename (SEQNUM.fits)
cxfloat8 unit vector of spherical co-ordinates pos.distance;pos.cartesian.x
cyfloat8 unit vector of spherical co-ordinates pos.distance;pos.cartesian.y
czfloat8 unit vector of spherical co-ordinates pos.distance;pos.cartesian.z
htmIDbigint8 Hierarchical Triangular Mesh (HTM) index, 20 deep, for equatorial co-ordinates pos.eq
rafloat8 R.A. (B1950) in HH MM SS.SS  
decfloat8 Dec. (B1950) in DD MM SS.S  
BJSELreal4 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)  
PROBreal4 psi classification parameter: for eyeballed galaxies: psi*1000 = (10000 + abs(jon) + psi*100); for eyeballed non-galaxies: psi*1000 = -(10000 + abs(jon) + psi*100)  
PARKreal4 k classification parameter = k / k_star  
PARMUreal4 mu classification parameter = mu / mu_star  
IGALint4 Final classification: -4 = noise; -3 = star + star; -2 = star + fuzz; -1 = star; 0 = galaxy + star merger; 1 = galaxy; 2 = galaxy + galaxy merger  
JONint4 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  
ORIENTreal4 Orientation measured in degrees clockwise from E to W: orient = 180/pi * atan(2*sxy/((sxx + syy)*(1 + e)-syy))  
ECCENTreal4 Eccentricity (e) e*200 = 200*(((sxx-syy)**2 + 4sxy**2)**0.5)/(sxx + syy)  
AREAreal4 Isophotal area in pixels  
X_BJreal4 Plate x_bj in 8 micron pixels  
Y_BJreal4 Plate y_bj in 8 micron pixels  
DXreal4 Distortion corrected difference (x_bj - x_R)*100  
DYreal4 Distortion corrected difference (y_bj - y_R)*100  
BJGreal4 Final bj magnitude without extinction correction  
RMAGreal4 Unmatched APM 'total' mag  
PMAGreal4 Unmatched raw APM profile integrated mag  
FMAGreal4 Unmatched raw APM 2" profile integrated mag  
SMAGreal4 Unmatched raw stellar mag (from APMCAL)  
REDMAGreal4 Not used  
IFIELDint4 UKST field  
IGFIELDint4 Galaxy number in UKST field  
NAMEvarchar10 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  
BJG_OLDreal4 Original bj magnitude without extinction correction (prior to re-calibration to BJG)  
BJSELOLDreal4 Original bj magnitude with extinction correction (prior to re-calibration to BJSEL); used to select survey sample  
BJG_100real4 100k release bj magnitude without extinction correction (prior to re-calibration to BJG)  
BJSEL_100real4 100k release bj magnitude with extinction correction (prior to re-calibration to BJSEL)  
Total length162