======================== zpix-SURVEY-PROGRAM.fits ======================== :Summary: Core redshift and targeting columns from the healpix-based redshift catalogs, one file per SURVEY and PROGRAM. :Naming Convention: ``zcatalog/v2/SURVEY/zpix-SURVEY-PROGRAM.fits``, where ``SURVEY`` is *e.g.* ``main`` or ``sv1`` and ``PROGRAM`` is *e.g.* ``bright`` or ``dark``. :Regex: ``zpix-(cmx|main|sv1|sv2|sv3|special)-(backup|bright|dark|other)\.fits`` :File Type: FITS, ~100 MB Contents ======== ====== ========= ======== ============================================================ Number EXTNAME Type Contents ====== ========= ======== ============================================================ HDU0_ PRIMARY IMAGE Empty HDU1_ ZCATALOG BINTABLE Core redshift catalog joined with targeting metadata ====== ========= ======== ============================================================ FITS Header Units ================= HDU0 ---- EXTNAME = PRIMARY Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ============ ================ ==== ======================= KEY Example Value Type Comment ============ ================ ==== ======================= CHECKSUM 9aaGCVYE9aaECUYE str HDU checksum DATASUM 0 str data unit checksum ZCATVER v2 str Version of zcatalog files ============ ================ ==== ======================= Empty HDU. .. _zcatalog-v2-zpix-hdu1: HDU1 ---- EXTNAME = ZCATALOG Core redshift and targeting columns from the :doc:`healpix-based Redrock redshift catalogs `. Imaging photometry columns are in the companion :doc:`zpix-SURVEY-PROGRAM-imaging.fits <./zpix-SURVEY-PROGRAM-imaging>` file. All remaining columns (full Redrock output, TSNR2, emission lines, QuasarNET, quality flags) are in :doc:`zpix-SURVEY-PROGRAM-extra.fits <./zpix-SURVEY-PROGRAM-extra>`. ``Z_BEST`` is the recommended redshift to use. It equals ``Z`` (Redrock) for most targets, but is set to ``Z_QSO`` (QuasarNET) for confirmed QSO targets where the two differ by more than 1000 km/s. ``Z_CONF`` encodes the overall confidence: 0 = no confidence; 1 = ZWARN==0 but not LSS-quality; 3 = passes LSS quality cuts for at least one extragalactic tracer class. ``TEMNAMnn`` and ``TEMVERnn`` record the Redrock template names and versions used for the redshift fits. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ============ ================ ==== ======================= KEY Example Value Type Comment ============ ================ ==== ======================= NAXIS1 261 int width of table in bytes NAXIS2 139728 int number of rows in table LONGSTRN OGIP 1.0 str RRVER 0.15.0 str Redrock version TEMNAM00 GALAXY str Redrock template 00 name TEMVER00 2.6 str Redrock template 00 version TEMNAM01 QSO:::HIZ str TEMVER01 0.1 str TEMNAM02 QSO:::LOZ str TEMVER02 1.0 str TEMNAM03 STAR:::A str TEMVER03 0.1 str TEMNAM04 STAR:::B str TEMVER04 0.1 str TEMNAM05 STAR:::CV str TEMVER05 0.1 str TEMNAM06 STAR:::F str TEMVER06 0.1 str TEMNAM07 STAR:::G str TEMVER07 0.1 str TEMNAM08 STAR:::K str TEMVER08 0.1 str TEMNAM09 STAR:::M str TEMVER09 0.1 str TEMNAM10 STAR:::WD str TEMVER10 0.1 str SPGRP healpix str Spectral grouping method HPXNSIDE 64 int Healpix nside HPXNEST T bool Nested healpix (not ring) SURVEY [1]_ main str DESI sub-survey (e.g. sv1, sv3, main) PROGRAM [1]_ dark str DESI program (e.g. dark, bright) CHECKSUM QA6lQ26iQ96iQ96i str HDU checksum DATASUM 4284326946 str data unit checksum ZCATVER v2 str Version of zcatalog files ============ ================ ==== ======================= Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ========================== =========== ======= ===================================================================================================================================== Name Type Units Description ========================== =========== ======= ===================================================================================================================================== TARGETID int64 Unique DESI target ID UNIQPIX [1]_ int32 Unique HEALPixel identifier encoding both pixel number and NSIDE (DR3+); HEALPIX and NSIDE are in the companion extra file HEALPIX [1]_ int32 HEALPixel containing this location at NSIDE=64 in the NESTED scheme (DR2 only) Z_BEST float64 Best redshift: equals Z (Redrock) for most targets, Z_QSO (QuasarNET) for confirmed QSOs where the two differ by >1000 km/s Z_CONF uint8 Redshift confidence: 0=no confidence, 1=low confidence (ZWARN==0), 3=high confidence (passes LSS quality cuts) ZERR_BEST float64 Redshift error for Z_BEST ZWARN_BEST int32 Redshift warning bitmask for Z_BEST SPECTYPE_BEST char[6] Spectral type for Z_BEST (e.g. GALAXY, QSO, STAR) SUBTYPE_BEST char[3] Spectral subtype for Z_BEST CHI2_BEST float32 Best fit chi squared for Z_BEST DELTACHI2_BEST float32 chi2 difference between first- and second-best fits for Z_BEST PETAL_LOC int16 Petal location [0-9] FIBER int32 Fiber ID on the CCDs [0-4999] COADD_FIBERSTATUS int32 bitwise-AND of input FIBERSTATUS TARGET_RA float64 deg Barycentric Right Ascension in ICRS TARGET_DEC float64 deg Barycentric Declination in ICRS DESINAME char[22] Human readable identifier of a sky location DESI JXXX.XXXX[+/-]YY.YYYY, where X,Y=truncated decimal TARGET_RA, TARGET_DEC, precise to 0.36 arcsec. Multiple objects can map to a single DESINAME if very close on the sky. OBJTYPE char[3] Object type: TGT, SKY, NON, BAD FIBERASSIGN_X float32 mm Fiberassign expected CS5 X location on focal plane FIBERASSIGN_Y float32 mm Fiberassign expected CS5 Y location on focal plane PRIORITY int32 Target current priority CMX_TARGET [1]_ int64 Target selection bitmask for commissioning SV1_DESI_TARGET [1]_ int64 DESI (dark time program) target selection bitmask for SV1 SV1_BGS_TARGET [1]_ int64 BGS (bright time program) target selection bitmask for SV1 SV1_MWS_TARGET [1]_ int64 MWS (bright time program) target selection bitmask for SV1 SV1_SCND_TARGET [1]_ int64 Secondary target selection bitmask for SV1 SV2_DESI_TARGET [1]_ int64 DESI (dark time program) target selection bitmask for SV2 SV2_BGS_TARGET [1]_ int64 BGS (bright time program) target selection bitmask for SV2 SV2_MWS_TARGET [1]_ int64 MWS (bright time program) target selection bitmask for SV2 SV2_SCND_TARGET [1]_ int64 Secondary target selection bitmask for SV2 SV3_DESI_TARGET [1]_ int64 DESI (dark time program) target selection bitmask for SV3 SV3_BGS_TARGET [1]_ int64 BGS (bright time program) target selection bitmask for SV3 SV3_MWS_TARGET [1]_ int64 MWS (bright time program) target selection bitmask for SV3 SV3_SCND_TARGET [1]_ int64 Secondary target selection bitmask for SV3 DESI_TARGET [1]_ int64 DESI (dark time program) target selection bitmask BGS_TARGET [1]_ int64 BGS (bright time program) target selection bitmask MWS_TARGET [1]_ int64 MWS (bright time program) target selection bitmask SCND_TARGET [1]_ int64 Secondary target selection bitmask COADD_NUMEXP int16 Number of exposures in coadd COADD_EXPTIME float32 s Summed exposure time for coadd COADD_NUMNIGHT int16 Number of nights in coadd COADD_NUMTILE int16 Number of tiles in coadd MIN_MJD float64 d Minimum value of the Modified Julian Date (when the shutter was open for the first exposure used in the coadded spectrum) MAX_MJD float64 d Maximum value of the Modified Julian Date (when the shutter was open for the last exposure used in the coadded spectrum) MEAN_MJD float64 d Mean value of the Modified Julian Date (when the shutter was open for exposures used in the coadded spectrum) GOOD_SPEC logical True if this is a science target with good hardware/fiber status EFFTIME_SPEC float32 s Effective exposure time for spectroscopy (from TSNR2_LRG; see Notes) ZCAT_NSPEC int16 Number of times this TARGETID appears in this catalog ZCAT_PRIMARY logical Boolean flag (True/False) for the primary coadded spectrum in this zcatalog ========================== =========== ======= ===================================================================================================================================== .. [1] Optional .. _`LS`: https://www.legacysurvey.org/ .. _`DR9 bitmasks page`: https://www.legacysurvey.org/dr9/bitmasks .. _`Gaia`: https://gea.esac.esa.int/archive/documentation//GDR2/Gaia_archive/chap_datamodel/sec_dm_main_tables/ssec_dm_gaia_source.html .. _SFD98: https://ui.adsabs.harvard.edu/abs/1998ApJ...500..525S/abstract Notes and Examples ================== * The targeting bitmasks ``DESI_TARGET``, ``BGS_TARGET``, ``MWS_TARGET``, and ``SCND_TARGET`` only apply to ``SURVEY="main"`` targets; they are `not` set for targets in other surveys. * Similarly, the ``SV1_DESI_TARGET`` etc. target masks are only set for the corresponding survey; there is no propagation of targeting bits across surveys. * ``GOOD_Z_{BGS,LRG,ELG,QSO}`` flags are in the companion :doc:`zpix-SURVEY-PROGRAM-extra.fits <./zpix-SURVEY-PROGRAM-extra>` file. * This file does not contain ``SV_NSPEC``, ``SV_PRIMARY``, ``MAIN_NSPEC``, or ``MAIN_PRIMARY``; these are added when zpix files are combined into :doc:`zall-pix-SPECPROD.fits <../zall/zall-pix-SPECPROD>`. * ``EFFTIME_SPEC`` is the effective exposure time computed as ``SNR2TIME * TSNR2_X``, where ``TSNR2_X`` is chosen by program: ``TSNR2_LRG`` for dark, ``TSNR2_BGS`` for bright, ``TSNR2_GPBBACKUP`` for backup. ``SNR2TIME`` is a per-tracer normalization factor from the TSNR ensemble template files in ``desimodel``. * For the SURVEY=cmx m33 tile (TILEID=80615) tile and all the SURVEY=sv1 tiles (except TILEID=80971-80976, the dc3r2 ones), proper-motion correction was applied at the :doc:`fiberassign ` design step; thus the following columns can have different values than in the :doc:`desitarget products `: ``TARGET_RA``, ``TARGET_DEC``, ``REF_EPOCH``, ``PLATE_RA``, ``PLATE_DEC``, and ``PLATE_REF_EPOCH``.