DEEP2 Galaxy Redshift Survey

 

Each entry in the redshift catalog is described by 36 tags. In the ASCII version of the catalog, each tag comprises a space-deliminated column. Note that there can be multiple entries in the redshift catalog for a given object. Each entry corresponds to a particular observation of that object designated by the DEIMOS slitmask (given by MASK), the slit number on the mask (SLIT), and the date of observation (MJD). Below, we provide a basic description of each tag. Note that in most instances (e.g., when computing rest-frame quantities) one should use the heliocentric-corrected redshift value (ZBEST) versus the observed value (Z). For full details regarding the catalog, refer to Newman et al. (2013). For more information on the MAGB, MAGR, MAGI, PGAL, and SFD_EBV tags, refer

to Coil et al. (2004) and the DR4 photometry primer.

Catalog Tag

OBJNO

RA

DEC

MAGB

MAGR

MAGI

MAGBERR

MAGRERR

MAGIERR

RG

E2

PA

PGAL

SFD_EBV

M_B

UB

OBJNAME

MASK

SLIT

DATE

MJD

SLITRA

SLITDEC

SLITPA

SLITLEN

Z

ZBEST

ZERR

ZQUALITY

CLASS

SUBCLASS

RCHI2

DOF

VDISP

VDISPERR

COMMENT

Data Type

LONG

DOUBLE

DOUBLE

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

STRING

LONG

LONG

STRING

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

FLOAT

INT

STRING

STRING

FLOAT

LONG

FLOAT

FLOAT

STRING

Brief Description

DEEP2 object number

Right Ascension (in decimal degrees, J2000)

Declination (in decimal degrees, J2000)

CFHT B-band magnitude (AB) from Coil et al. 2004

CFHT R-band magnitude (AB) from Coil et al. 2004

CFHT I-band magnitude (AB) from Coil et al. 2004

B-band magnitude error

R-band magnitude error

I-band magnitude error

estimated R-band radius of object
    (sigma of Guassian fit in units of pixels --- 0.207”/pix)

ellipticity defined as E2 = (1 - b/a)

object PA (degrees E of N)

the probability (0 - 1) that the sources is a galaxy for unresolved galaxies, 3 if resolved

E(B-V) from Schlegel, Finkbeiner, and Davis dust map

absolute B-band magnitude (AB, h = 1) from Willmer et al. (2006)

rest-frame U-B color (AB) from Willmer et al. (2006)

the 8-digit DEEP2 object id
    (not always the same as OBJNO)

the DEEP2/DEEP3 slitmask number on which the object was observed

the slitlet number (on mask MASKNAME) in which the object was placed

Date on which the mask was observed (YYYY-MM-DD)

Modified Julian date of observation

RA of slit center

Dec of slit center

PA (degrees E of N) of slit

length of slit (arcsec)

observed best-fitting redshift

best redshift (corrected for heliocentric motion)

redshift error (zerr < 0 indicates problematic z fit)

redshift quality code, Q

type of best-fitting template (e.g., GALAXY or STAR)

coarse classification for stellar templates

reduced chi-squared value for the redshift fit

degrees of freedom for redshift fit

velocity dispersion in km/s

error in velocity dispersion

comment field

The DEEP2 DR4 Redshift Catalog Tags

Data Release 4

† ⎯ The CFHT 12K BRI catalogs are created on a pointing-by-pointing bases and not at a field-by-field level (for more info regarding the DEEP2 fields and pointings, refer to the description of the photometric catalogs and here). For objects that fall in the regions of overlap between the various photometric pointings within a given field, the objects can appear in multiple photometric catalogs (e.g., in pcat.41.fits and pcat.42.fits), being assigned different 8-digit DEEP2 identification numbers in each catalog. These duplications have been resolved such that a unique identifier is assigned. This is the 8-digit ID given in the “OBJNO” field. However, the slitmasks are designed on a pointing-by-pointing basis, so objects are actually targeted based on their id numbers in a particular pointing. Most importantly, since the spec2d data reduction pipeline draws the object id information from the slitmask design files, the object id in the “spec1d” files is this pointing-specific number. In order to facilitate matching of entries in the redshift catalog to 1-d spectral files, the “OBJNAME” field is included, which gives the pointing-specific id number. Thus, for a given entry in the redshift catalog, the spec1d file will be named “spec1d.MASK.SLIT.OBJNAME.fits”, following the formatting detailed here.


‡ ⎯  It should be noted that the CLASS tag only indicates the best-fitting template; many AGN (both broad- and narrow-line) in the DEEP2 sample will have 'GALAXY' as their class.