====================== exposure-qa-EXPID.fits ====================== :Summary: These files contain the per-exposure QA measurements. Those are propagated when making coadd reductions, and helps to decide during operations if the observation is valid or not. :Naming Convention: ``exposure-qa-{expid}``, where ``{expid}`` is the 8-digit exposure ID. :Regex: ``exposure-qa-[0-9]{8}\.fits`` :File Type: FITS, 441 KB Contents ======== ====== ======= ======== =================== Number EXTNAME Type Contents ====== ======= ======== =================== HDU0_ IMAGE Keywords only HDU1_ FIBERQA BINTABLE Per-fiber information table HDU2_ PETALQA BINTABLE Per-petal information table ====== ======= ======== =================== FITS Header Units ================= HDU0 ---- No data, checksum/datasum header keywords only. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ======== ================ ==== ============================================== KEY Example Value Type Comment ======== ================ ==== ============================================== CHECKSUM C4gFE4Z9C4fCC4Z9 str HDU checksum updated 2021-07-16T14:31:54 DATASUM 0 str data unit checksum updated 2021-07-16T14:31:54 ======== ================ ==== ============================================== Empty HDU. HDU1 ---- EXTNAME = FIBERQA This table contains the per-fiber information which helps to decide if the observation is valid or not. That information is also used to define some column content of the PETALQA extension. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ============= =================== ===== ============================================== KEY Example Value Type Comment ============= =================== ===== ============================================== NAXIS1 86 int length of dimension 1 NAXIS2 5000 int length of dimension 2 NIGHT 20210514 int Exposure night EXPID 88364 int Exposure ID NGOODFIB 4611 int Number of fibers with EFFTIME_SPEC above the threshold NGOODPET 10 int Number of petals with good fibers WORSTRDN 5.072375888924774 float Worst read noise for all amplifiers of all cameras FPRMS2D 0.01157238915902728 float [mm] RMS of the positioners accuracy (measured-requested) in the CS5 location of the focal plane PMINEXPF [1]_ 0.8370916420971888 float Deprecated PMAXEXPF [1]_ 1.27911264193688 float Deprecated EFFTIME 217.9705047607422 float [s] Spectroscopic effective time TILEID 21181 int Tile ID EXPTIME 589.277 float [s] Tile exposure time MJD-OBS 59349.20075297 float [d] Modified Julian Date of observation TARGTRA 199.993521 float [deg] Target right ascension (to TCS) TARGTDEC 32.447031 float [deg] Target declination (to TCS) MOUNTEL 84.320435 float [deg] Mount elevation angle MOUNTHA -6.689017 float [deg] Mount hour angle AIRMASS 1.004188 float Airmass ETCTEFF [1]_ 1015.311096 float [s] Effective time computed (on-the-fly) by the ETC TILERA 199.992 float [deg] Tile center Right Ascension TILEDEC 32.447 float [deg] Tile center Declination GOALTIME [1]_ 180.0 float [s] Aimed EFFTIME_SPEC GOALTYPE [1]_ BRIGHT str Sky conditions used for some noise estimation FAPRGRM [1]_ bright str Program to which this tile belongs SURVEY [1]_ main str Survey of origin of the targets EBVFAC [1]_ 1.02512649227135 float 10.0 ** (2.165 * median(EBV) / 2.5)) MINTFRAC [1]_ 0.85 float Fraction of GOALTIME to be reached by EFFTIME_SPEC to consider the tile has completed CHECKSUM YP2AYM16YM1AYM13 str HDU checksum updated 2021-07-16T14:31:54 DATASUM 2084006317 str data unit checksum updated 2021-07-16T14:31:54 ============= =================== ===== ============================================== Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ============= ======= ===== =========== Name Type Units Description ============= ======= ===== =========== TARGETID int64 Unique target ID 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] TARGET_RA float64 deg Target Right Ascension TARGET_DEC float64 deg Target Declination FIBER_X float64 mm Fiber CS5 X location on focal plane FIBER_Y float64 mm Fiber CS5 Y location on focal plane DELTA_X float64 mm Fiber difference between measured and requested CS5 X location on focal plane DELTA_Y float64 mm Fiber difference between measured and requested CS5 Y location on focal plane EBV float32 mag Galactic extinction E(B-V) reddening QAFIBERSTATUS int32 Fiber status bitmask, inflated with further QA diagnoses EFFTIME_SPEC float32 s Spectroscopic effective time, based on template-based squared signal-to-noise ratio ============= ======= ===== =========== HDU2 ---- EXTNAME = PETALQA This table contains some per-petal QA information which helps to decide if the observation is valid or not, and if a petal should be considered as "bad" (i.e. as if it would not have been observed), because of a too-low quality. Required Header Keywords ~~~~~~~~~~~~~~~~~~~~~~~~ .. collapse:: Required Header Keywords Table .. rst-class:: keywords ======== ================ ==== ============================================== KEY Example Value Type Comment ======== ================ ==== ============================================== NAXIS1 62 int length of dimension 1 NAXIS2 10 int length of dimension 2 CHECKSUM 8aaf9WRc8aXc8WXc str HDU checksum updated 2021-07-16T14:31:54 DATASUM 666368269 str data unit checksum updated 2021-07-16T14:31:54 ======== ================ ==== ============================================== Required Data Table Columns ~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. rst-class:: columns ============== ======= ===== =========== Name Type Units Description ============== ======= ===== =========== PETAL_LOC int16 Petal location [0-9] WORSTREADNOISE float32 Worst read noise (each individual value being the worst across amplifiers) NGOODPOS int16 Number of valid positioners NGOODFIB int16 Number of good fibers NSTDSTAR int16 Number of standard stars used by the spectroscopic pipeline for calibration STARRMS float32 RMS of the r-band flux ratio of standard stars TSNR2FRA [1]_ float32 Deprecated EFFTIME_SPEC float32 s Median of the EFFTIME_SPEC values for all good fibers from that petal NCFRAME int16 Number of cframe files for that petal BSKYTHRURMS float32 Sky throuput RMS for the b-camera BSKYCHI2PDF float32 Reduced chi2 for the sky fibers for the b-camera RSKYTHRURMS float32 Sky throuput RMS for the r-camera RSKYCHI2PDF float32 Reduced chi2 for the sky fibers for the r-camera ZSKYTHRURMS float32 Sky throuput RMS for the z-camera ZSKYCHI2PDF float32 Reduced chi2 for the sky fibers for the z-camera BTHRUFRAC float32 Relative (single petal vs. all petals) throughput for the b-camera RTHRUFRAC float32 Relative (single petal vs. all petals) throughput for the r-camera ZTHRUFRAC float32 Relative (single petal vs. all petals) throughput for the z-camera ============== ======= ===== =========== .. [1] Optional Notes and Examples ================== * These ``exposure-qa-{expid}`` files are used to compute several of the :doc:`tile-qa-TILEID-GROUPID <../../../tiles/GROUPTYPE/TILEID/GROUPID/tile-qa-TILEID-GROUPID>` entries. * The QAFIBERSTATUS bitmasks are defined here :doc:`bitmasks <../../../../../../bitmasks>`. * Some FIBERQA extension header keywords are originally coming from the :doc:`fiberassign-TILEID <../../../../../DESI_TARGET/fiberassign/tiles/TILES_VERSION/TILEXX/fiberassign-TILEID>` file (TILEID, TILERA, TILEDEC, GOALTIME, GOALTYPE, FAPRGRM, SURVEY, EBVFAC, MINTFRAC). * The FIBERQA EFFTIME_SPEC is proportional to the TSNR2 values in the TSNR2 extension of the :doc:`redrock-SPECTROGRAPH-TILEID-GROUPID <../../../tiles/GROUPTYPE/TILEID/GROUPID/redrock-SPECTROGRAPH-TILEID-GROUPID>` file; for the BACKUP and BRIGHT programs, the TSNR2_BGS is used; for the DARK program, the TSNR2_ELG or TSNR2_LRG is used. * 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``.