================================== redrock-SURVEY-PROGRAM-PIXNUM.fits ================================== :Summary: Redshifts and spectral classifications from Redrock. :Naming Convention: ``redrock-SURVEY-PROGRAM-PIXNUM.fits``, where ``SURVEY`` is *e.g.* ``main`` or ``sv1``, ``PROGRAM`` is *e.g.* ``bright or ``dark`` and ``PIXNUM`` is the HEALPixel number. :Regex: ``redrock-(cmx|main|special|sv1|sv2|sv3)-(backup|bright|dark|other)-[0-9]+\.fits`` :File Type: FITS, 354 KB This file contains spectral classifications and redshifts for spectra coadded across exposures and tiles covering a given HEALpix pixel. For a similar file that only combines data across a single tile but not across tiles, see :doc:`tile-based Redrock files `. Contents ======== ====== ============ ======== =================== Number EXTNAME Type Contents ====== ============ ======== =================== HDU0_ IMAGE Keywords only HDU1_ REDSHIFTS BINTABLE Table with redshifts and spectral classifications HDU2_ FIBERMAP BINTABLE Target photometry and metadata HDU3_ EXP_FIBERMAP BINTABLE Per-exposure entries from input fibermaps HDU4_ TSNR2 BINTABLE Template signal-to-noise values from input SCORES table ====== ============ ======== =================== FITS Header Units ================= HDU0 ---- Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ======== ============= ==== =============== KEY Example Value Type Comment ======== ============= ==== =============== 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 str TEMVER01 0.1 str TEMNAM02 STAR:::A str TEMVER02 0.1 str TEMNAM03 STAR:::B str TEMVER03 0.1 str TEMNAM04 STAR:::CV str TEMVER04 0.1 str TEMNAM05 STAR:::F str TEMVER05 0.1 str TEMNAM06 STAR:::G str TEMVER06 0.1 str TEMNAM07 STAR:::K str TEMVER07 0.1 str TEMNAM08 STAR:::M str TEMVER08 0.1 str TEMNAM09 STAR:::WD str TEMVER09 0.1 str SPGRP healpix str Grouping method SPGRPVAL 32637 int Grouping value (same as HPXPIXEL) HPXPIXEL 36637 int Healpix pixel HPXNSIDE 64 int Healpix nside HPXNEST True str Healpix nested (not ring) SURVEY sv1 str DESI survey (sv1, sv3, main, ...) PROGRAM dark str DESI program (dark, bright, ...) ======== ============= ==== =============== Empty HDU. HDU1 ---- EXTNAME = REDSHIFTS Spectral classifications and redshifts from Redrock. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ====== ============= ==== ===================== KEY Example Value Type Comment ====== ============= ==== ===================== NAXIS1 170 int Width of table in bytes NAXIS2 415 int Number of targets in table ====== ============= ==== ===================== Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ========= =========== ===== ========================================================= Name Type Units Description ========= =========== ===== ========================================================= TARGETID int64 Target ID for this row CHI2 float64 Best fit :math:`\chi^2` COEFF float64[10] Redrock template coefficients Z float64 Best fit redshift ZERR float64 Uncertainty on best fit redshift ZWARN int64 Warning flags; 0 is good NPIXELS int64 Number of unmasked pixels contributing to the Redrock fit SPECTYPE char[6] Spectral type SUBTYPE char[20] Spectral subtype (maybe blank) NCOEFF int64 Number of Redrock template coefficients DELTACHI2 float64 :math:`\Delta \chi^2` to next best fit ========= =========== ===== ========================================================= HDU2 ---- EXTNAME = FIBERMAP Fibermap with target metadata such as photometry and target selection bits. This table is row-matched to the REDSHIFTS table. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ====== ============= ==== ===================== KEY Example Value Type Comment ====== ============= ==== ===================== NAXIS1 317 int Width of table in bytes NAXIS2 415 int Number of targets in table. ====== ============= ==== ===================== Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ========================== ======= ============ =============================================================================================================================== Name Type Units Description ========================== ======= ============ =============================================================================================================================== TARGETID int64 Unique DESI target ID 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 PMRA float32 mas yr^-1 proper motion in the +RA direction (already including cos(dec)) PMDEC float32 mas yr^-1 Proper motion in the +Dec direction REF_EPOCH float32 yr Reference epoch for Gaia/Tycho astrometry. Typically 2015.5 for Gaia FA_TARGET int64 Targeting bit internally used by fiberassign (linked with FA_TYPE) FA_TYPE binary Fiberassign internal target type (science, standard, sky, safe, suppsky) OBJTYPE char[3] Object type: TGT, SKY, NON, BAD SUBPRIORITY float64 Random subpriority [0-1) to break assignment ties OBSCONDITIONS int32 Bitmask of allowed observing conditions RELEASE int16 Imaging surveys release ID BRICKID int32 Brick ID from tractor input BRICK_OBJID int32 Imaging Surveys OBJID on that brick MORPHTYPE char[4] Imaging Surveys morphological type from Tractor FLUX_G float32 nanomaggy Flux in the Legacy Survey g-band (AB) FLUX_R float32 nanomaggy Flux in the Legacy Survey r-band (AB) FLUX_Z float32 nanomaggy Flux in the Legacy Survey z-band (AB) FLUX_IVAR_G float32 nanomaggy^-2 Inverse variance of FLUX_G (AB) FLUX_IVAR_R float32 nanomaggy^-2 Inverse variance of FLUX_R (AB) FLUX_IVAR_Z float32 nanomaggy^-2 Inverse variance of FLUX_Z (AB) MASKBITS int16 Bitwise mask from the imaging indicating potential issue or blending REF_ID int64 Tyc1*1,000,000+Tyc2*10+Tyc3 for Tycho-2; “sourceid” for Gaia DR2 REF_CAT char[2] Reference catalog source for star: “T2” for Tycho-2, “G2” for Gaia DR2, “L2” for the SGA, empty otherwise GAIA_PHOT_G_MEAN_MAG float32 mag Gaia G band magnitude GAIA_PHOT_BP_MEAN_MAG float32 mag Gaia BP band magnitude GAIA_PHOT_RP_MEAN_MAG float32 mag Gaia RP band magnitude PARALLAX float32 mas Reference catalog parallax BRICKNAME char[8] Brick name from tractor input EBV float32 mag Galactic extinction E(B-V) reddening from SFD98 FLUX_W1 float32 nanomaggy WISE flux in W1 (AB) FLUX_W2 float32 nanomaggy WISE flux in W2 (AB) FLUX_IVAR_W1 float32 nanomaggy^-2 Inverse variance of FLUX_W1 (AB) FLUX_IVAR_W2 float32 nanomaggy^-2 Inverse variance of FLUX_W2 (AB) FIBERFLUX_G float32 nanomaggy Predicted g-band flux within a fiber of diameter 1.5 arcsec from this object in 1 arcsec Gaussian seeing FIBERFLUX_R float32 nanomaggy Predicted r-band flux within a fiber of diameter 1.5 arcsec from this object in 1 arcsec Gaussian seeing FIBERFLUX_Z float32 nanomaggy Predicted z-band flux within a fiber of diameter 1.5 arcsec from this object in 1 arcsec Gaussian seeing FIBERTOTFLUX_G float32 nanomaggy Predicted g-band flux within a fiber of diameter 1.5 arcsec from all sources at this location in 1 arcsec Gaussian seeing FIBERTOTFLUX_R float32 nanomaggy Predicted r-band flux within a fiber of diameter 1.5 arcsec from all sources at this location in 1 arcsec Gaussian seeing FIBERTOTFLUX_Z float32 nanomaggy Predicted z-band flux within a fiber of diameter 1.5 arcsec from all sources at this location in 1 arcsec Gaussian seeing SERSIC float32 Power-law index for the Sersic profile model (MORPHTYPE=”SER”) SHAPE_R float32 arcsec Half-light radius of galaxy model (>0) SHAPE_E1 float32 Ellipticity component 1 of galaxy model for galaxy type MORPHTYPE SHAPE_E2 float32 Ellipticity component 2 of galaxy model for galaxy type MORPHTYPE PHOTSYS char[1] 'N' for the MzLS/BASS photometric system, 'S' for DECaLS PRIORITY_INIT int64 Target initial priority from target selection bitmasks and OBSCONDITIONS NUMOBS_INIT int64 Initial number of observations for target calculated across target selection bitmasks and OBSCONDITIONS DESI_TARGET int64 DESI (dark time program) target selection bitmask BGS_TARGET int64 BGS (Bright Galaxy Survey) target selection bitmask MWS_TARGET int64 Milky Way Survey targeting bits SCND_TARGET int64 Target selection bitmask for secondary programs PLATE_RA float64 deg Barycentric Right Ascension in ICRS to be used by PlateMaker PLATE_DEC float64 deg Barycentric Declination in ICRS to be used by PlateMaker 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 MEAN_DELTA_X float32 mm Mean (over exposures) fiber difference requested - actual CS5 X location on focal plane RMS_DELTA_X float32 mm RMS (over exposures) of the fiber difference between measured and requested CS5 X location on focal plane MEAN_DELTA_Y float32 mm Mean (over exposures) fiber difference requested - actual CS5 Y location on focal plane RMS_DELTA_Y float32 mm RMS (over exposures) of the fiber difference between measured and requested CS5 Y location on focal plane MEAN_FIBER_RA float64 deg Mean (over exposures) RA of actual fiber position STD_FIBER_RA float32 arcsec Standard deviation (over exposures) of RA of actual fiber position MEAN_FIBER_DEC float64 deg Mean (over exposures) DEC of actual fiber position STD_FIBER_DEC float32 arcsec Standard deviation (over exposures) of DEC of actual fiber position MEAN_PSF_TO_FIBER_SPECFLUX float32 Mean of input exposures fraction of light from point-like source captured by 1.5 arcsec diameter fiber given atmospheric seeing ========================== ======= ============ =============================================================================================================================== HDU3 ---- EXTNAME = EXP_FIBERMAP Fibermap entries that vary from exposure to exposure, e.g. what exposures were include in the coadd and what focalplane (x,y) each target was located at for each exposure. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ====== ============= ==== ===================== KEY Example Value Type Comment ====== ============= ==== ===================== NAXIS1 162 int Width of table in bytes NAXIS2 415 int Number of input target-exposures = rows in table ====== ============= ==== ===================== Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ===================== ======= ======== ======================================================================================================= Name Type Units Description ===================== ======= ======== ======================================================================================================= TARGETID int64 Unique DESI target ID PRIORITY int32 Target current priority SUBPRIORITY float64 Random subpriority [0-1) to break assignment ties NIGHT int32 EXPID int32 DESI Exposure ID number MJD float64 Modified Julian Date when shutter was opened for this exposure TILEID int32 Unique DESI tile ID EXPTIME float64 s Length of time shutter was open PETAL_LOC int16 Petal location [0-9] DEVICE_LOC int32 Device location on focal plane [0-523] LOCATION int64 Location on the focal plane PETAL_LOC*1000 + DEVICE_LOC FIBER int32 Fiber ID on the CCDs [0-4999] FIBERSTATUS int32 Fiber status mask. 0=good FIBERASSIGN_X float32 mm Fiberassign expected CS5 X location on focal plane FIBERASSIGN_Y float32 mm Fiberassign expected CS5 Y location on focal plane LAMBDA_REF float32 Angstrom Requested wavelength at which targets should be centered on fibers PLATE_RA float64 deg Barycentric Right Ascension in ICRS to be used by PlateMaker PLATE_DEC float64 deg Barycentric Declination in ICRS to be used by PlateMaker NUM_ITER int64 Number of positioner iterations FIBER_X float64 mm CS5 X location requested by PlateMaker FIBER_Y float64 mm CS5 Y location requested by PlateMaker DELTA_X float64 mm CS5 X requested minus actual position DELTA_Y float64 mm CS5 Y requested minus actual position FIBER_RA float64 deg RA of actual fiber position FIBER_DEC float64 deg DEC of actual fiber position PSF_TO_FIBER_SPECFLUX float64 fraction of light from point-like source captured by 1.5 arcsec diameter fiber given atmospheric seeing ===================== ======= ======== ======================================================================================================= HDU4 ---- EXTNAME = TSNR2 Template signal-to-noise squared. These quantities weight the observed (S/N)^2 by which wavelengths matter most for different target types, e.g. QSOs weight blue wavelengths more while ELGs weight redder wavelengths more due to the wavelengths of the observed emission lines. For more details, see section 4.14 of `Guy et al 2023 `_. This table is row-matched to the REDSHIFTS table. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ====== ============= ==== ===================== KEY Example Value Type Comment ====== ============= ==== ===================== NAXIS1 136 int Width of table in bytes. NAXIS2 415 int Number of targets = number of table rows. ====== ============= ==== ===================== Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ================= ======= ===== ====================================== Name Type Units Description ================= ======= ===== ====================================== TARGETID int64 Unique DESI target ID TSNR2_GPBDARK_B float32 TSNR2_ELG_B float32 ELG B template (S/N)^2 TSNR2_GPBBRIGHT_B float32 TSNR2_LYA_B float32 LYA B template (S/N)^2 TSNR2_BGS_B float32 BGS B template (S/N)^2 TSNR2_GPBBACKUP_B float32 TSNR2_QSO_B float32 QSO B template (S/N)^2 TSNR2_LRG_B float32 LRG B template (S/N)^2 TSNR2_GPBDARK_R float32 TSNR2_ELG_R float32 ELG R template (S/N)^2 TSNR2_GPBBRIGHT_R float32 TSNR2_LYA_R float32 LYA R template (S/N)^2 TSNR2_BGS_R float32 BGS R template (S/N)^2 TSNR2_GPBBACKUP_R float32 TSNR2_QSO_R float32 QSO R template (S/N)^2 TSNR2_LRG_R float32 LRG R template (S/N)^2 TSNR2_GPBDARK_Z float32 TSNR2_ELG_Z float32 ELG Z template (S/N)^2 TSNR2_GPBBRIGHT_Z float32 TSNR2_LYA_Z float32 LYA Z template (S/N)^2 TSNR2_BGS_Z float32 BGS Z template (S/N)^2 TSNR2_GPBBACKUP_Z float32 TSNR2_QSO_Z float32 QSO Z template (S/N)^2 TSNR2_LRG_Z float32 LRG Z template (S/N)^2 TSNR2_GPBDARK float32 TSNR2_ELG float32 ELG template (S/N)^2 summed over B,R,Z TSNR2_GPBBRIGHT float32 TSNR2_LYA float32 LYA template (S/N)^2 summed over B,R,Z TSNR2_BGS float32 BGS template (S/N)^2 summed over B,R,Z TSNR2_GPBBACKUP float32 TSNR2_QSO float32 QSO template (S/N)^2 summed over B,R,Z TSNR2_LRG float32 LRG template (S/N)^2 summed over B,R,Z ================= ======= ===== ====================================== Notes and Examples ================== The REDSHIFTS, FIBERMAP, and TSNR2 tables are row-matched with one row per target. They also include a TARGETID column for confirmation and database-like joins with other tables. The EXP_FIBERMAP HDU has one row per target-exposure, and thus will have multiple entries per target when a target was observed on multiple input exposures. This file is for redshifts from an individual healpixel. For a concatenation of all such files, see the :doc:`redshift catalogs ` (the zpix files in particular). 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``. For targets with a non-zero proper motion, ``FIBER_RA`` and ``FIBER_DEC`` refer to the position at the reference epoch (but note that the proper-motion correction has been applied at the time of the observation, it is just not recorded in ``FIBER_RA`` and ``FIBER_DEC``).