Data model: ssppTargets

General description: The SEGUE targeting information for all fibers associated with a given data release. The format is the same as the full target files. For the SEGUE-2 spectroscopic parameters associated with each star, see the associated ssppOut file. This file is simply gathered from the matches to each individual plate, the segueTargetPlate files.

Let us give an overview of the structure of the targeting files. The original SEGUE and SEGUE-2 target files have been all homogenized into a single file type, which are stored in separate directories for SEGUE-1 and SEGUE-2. We do not recommend that the casual user dig too deeply into those file types, but we keep and document them for archival purposes.

We recommend using the version of these files which have been matched to the spectra that were actually taken. All such files live in the directory tree under $SSPP_REDUX/targets. There is a full list of potential targets contained in the set of segueTarget files, which includes information about which targets passed selection and which actually achieved spectra. From these full lists we produce segueTargetPlate files, which list the targets that were actually used for each fiber on that plate. Finally, we gather the individual plate information into the ssppTargets file to yield all of the target information for all plates in a single file.

Naming convention: ssppTargets-DRNAME.fits

Approximate size: 1 Gbytes.

File type: FITS

Read by products: sas

Written by products: sas

Required column names

• RUN (int64): Run number
• RERUN (int64): Rerun number
• CAMCOL (int64): Camera column number
• FIELD (int64): Field number
• OBJ (int64): Object
• RA (float64): RA (degree)
• DEC (float64): Dec (degree)
• L (float64): Galactic longitude (degree)
• B (float64): Galactic latitude (degree)
• FIBERMAG (float32): u band fiber magnitudue (mag)
• PSFMAG (float32): u band PSF magnitude (mag)
• EXTINCTION (float32): u band extinction (mag)
• ROWC (int32): row centroid (pix)
• COLC (int32): column centroid (pix)
• TYPE (int32): object type from photometric reductions
• FLAGS (int64): combined flags from all bands
• FLAGS (int64): u band flag
• PSFMAGERR (float32): Error in u band PSF magnitude (mag)
• SPECOBJID (int64): Spectroscopic object ID
• PLATE (int64): Plate number
• MJD (int64): Modified Julian Date
• FIBERID (int64): Fiber number
• BESTOBJID (int64): Best object ID
• TARGETOBJID (int64): Target object ID
• SEGUEPRIMTARGET (int32): SEGUE primary target
• SEGUESECTARGET (int32): SEGUE secondary target
• PRIMTARGET (int32): Primary target
• SECTARGET (int32): Secondary target
• sppparams_sna (float64): Average signal-to-noise ratio. This is SNA from the sppParams table
• PMOBJID (int64): Proper motion object ID
• MATCH (int64): Number of objects in USNO-B which matched this object within a 1 arcsec radius. If negative, then the nearest matching USNO-B object itself matched more than 1 SDSS object.
• DELTA (float64): Distance between this object and the nearest matching USNO-B object (arcsec)
• PML (float64): Proper motion in Galactic longitude (mas/yr)
• PMB (float64): Proper motion in Galactic latitude (mas/yr)
• PMRA (float64): Proper motion in RA (mas/yr)
• PMDEC (float64): Proper motion in DEC (mas/yr)
• PMRAERR (float64): Proper motion error in RA (mas/yr)
• PMDECERR (float64): Proper motion error in DEC (mas/yr)
• PMSIGRA (float64): RMS residual for the proper motion fit in R.A. (mas)
• PMSIGDEC (float64): RMS residual for the proper motion fit in Dec. (mas)
• NFIT (int32): Number of detections used in the fit including the SDSS detection (thus, the number of plates the object was detected on in USNO-B plus one).
• DIST22 (float64): Distance to the nearest neighbor with g < 22 (arcsec)
• DIST20 (float64): Distance to the nearest neighbor with g < 20 (arcsec)
• uMAG (float32): u extinction-corrected (SFD 98) psf magnitude (mag)
• gMAG (float32): g extinction-corrected (SFD 98) psf magnitude (mag)
• rMAG (float32): r extinction-corrected (SFD 98) psf magnitude (mag)
• iMAG (float32): i extinction-corrected (SFD 98) psf magnitude (mag)
• zMAG (float32): z extinction-corrected (SFD 98) psf magnitude (mag)
• umg (float32): u-g, extinction corrected magnitudes (mag)
• gmr (float32): g-r, extinction corrected magnitudes (mag)
• rmi (float32): r-i, extinction corrected magnitudes (mag)
• imz (float32): i-z, extinction corrected magnitudes (mag)
• gmi (float32): g-i, extinction corrected magnitudes (mag)
• umgERR (float32): PSFMAGERR_u and PSFMAGERR_g added in quadrature (mag)
• gmrERR (float32): PSFMAGERR_g and PSFMAGERR_r added in quadrature (mag)
• rmiERR (float32): PSFMAGERR_r and PSFMAGERR_i added in quadrature (mag)
• imzERR (float32): PSFMAGERR_i and PSFMAGERR_z added in quadrature (mag)
• psfmag_umg (float32): psfmag_u-psfmag_g, no extinction correction (mag)
• psfmag_gmr (float32): psfmag_g-psfmag_r, no extinction correction (mag)
• psfmag_rmi (float32): psfmag_r-psfmag_i, no extinction correction (mag)
• psfmag_imz (float32): psfmag_i-psfmag_z, no extinction correction (mag)
• psfmag_gmi (float32): psfmag_g-psfmag_i, no extinction correction (mag)
• lcolor (float32): -0.436*uMag+1.129*gMag-0.119*rMag-0.574*iMag+0.1984 (Lenz et al.1998) (mag)
• scolor (float32): -0.249*uMag+0.794*gMag-0.555*rMag+0.234+0.011*p1s-0.010 (Helmi et al. 2003) used in SEGUE-1 target selection, unused in SEGUE-2 (mag)
• p1s (float32): 0.91*umg+0.415*umg-1.280 (Helmi et al. 2003) used in SEGUE-1 target selection, unused in SEGUE-2 (mag)
• TOTALPM (float32): sqrt(PMRA*PMRA+PMDEC*PMDEC), in mas/year (mas)
• Hg (float32): reduced proper motion, gMag+5*log10(TOTALPM/1000)+5 (mag)
• Mi (float32): 4.471+7.907*imz-0.837*imz*imz used in SEGUE-1 target selection, unused in SEGUE-2 (mag)
• DISTi (float32): 10^((iMag-Mi+5)/5.0) used in SEGUE-1 target selection, unused in SEGUE-2 (mag)
• Hr (float32): reduced pm (uncorr r): PSFMAG_r+5*log10(TOTALPM/1000)+5 (mag)
• vmi_trans1 (float32): V-I from VMAG_TRANS-(iMag-0.337*rmi-0.37) (mag)
• vmi_trans2 (float32): V-I from 0.877*gmr+0.358 (mag)
• vmag_trans (float32): V mag from gMag - 0.587*gmr -0.011 (mag)
• distv_kpc (float32): 10^(dmV/5.-2.) where VMAG_TRANS-(3.37*VMI_TRANS1+2.89) (kpc)
• vtrans_galrest (float32): transvere velocity, km/s, derived from TOTALPM and DISTV_KPC, in a frame at rest w.r.t the Galaxy (km)
• mutrans_galradrest (float32): derived PM (mas/year) perpendicular to the Galactocentric radial vector, assuming all motion is along a Galactocentric radial vector, in a frame at rest w.r.t the Galaxy (mas)
• murad_galradrest (float32): derived PM (mas/year) along the Galactocentric radial vector, assuming all motion is along a Galactocentric radial vector, in a frame at rest w.r.t the Galaxy (mas)
• vtot_galradrest (float32): total velocioty, km/s, derived from TOTALPM and DISTV_KPC, in a frame at rest w.r.t the Galaxy (km)
• mg_tohv (float32): 5.7 + 10.0*(GMR - 0.375) (mag)
• vtrans_tohv (float32): transverse velocity in Galactocentric coords, using the distance estimate from MG_TOHV which is appropriate for old stars near the MSTO and corrected for peculiar solar motion 16.6 km/s toward RA,Dec 267.5,28.1 (km)
• pm1sigma_tohv (float32): Estimate of the 1-sigma error in total proper motion at this r magnitude. Formula is sqrt(4.56*4.56 + frate*2.30*2.30), where frate is 10^(0.4*(rMag-19.5)). The constants come from the Munn et al. 2004 (AJ, 127, 3034) paper describing the recalibration of USNOB with SDSS. (mas)
• v1sigmaerr_tohv (float32): The corresponding 1-sigma error in the transverse velocity based on PM1SIGMA_TOHV and the the distance estimate using MG_TOHV (km)
• segue2_target1 (int32): bitmask that records the category or categories for which this object passed the selection criteria
• segue2_target2 (int32): bitmask that records the category or categories of "standards" for the pipeline, special calibration targets like Stetson standards or globular cluster stars, for which this object passed the selection criteria
• TARGET_VERSION (string): version of target used

Example file: ssppTargets-testbed8.fits