Index: /trunk/ppMops/ICDlite.txt =================================================================== --- /trunk/ppMops/ICDlite.txt (revision 25135) +++ /trunk/ppMops/ICDlite.txt (revision 25135) @@ -0,0 +1,150 @@ +== General notes == + +Though efforts have been made to avoid this from occurring, where +header keyword names are longer than the usual 8 character maximum, +the HIERARCH convention will be used. + +Celestial coordinates are in ICRS. + +Magnitudes are AB magnitudes (flux zero point is 3631 Jy). + +Unless otherwise noted, error values are statistical only, and include +no contribution by systematic errors. + +== Primary header == + +The primary header will not contain any information beyond that +written automatically by cfitsio, and is present only for compliance +with the FITS standard. + +== FITS table == + +The FITS table will include all detections within an exposure. + +Duplicates from overlapping skycells will have been filtered out by +IPP, with the measurements from the source closest to the centre of a +skycell included (and all others discarded). + +=== Header === + +The header will contain information relevant to the exposure as a whole. + + * Version information + * SWSOURCE (string): source of software (e.g., "60eb6cdc-a59c-4636-a4e0-dba66a9721fd") + * SWVERSN (string): version of software (e.g., "trunk/ppMops@24658") + + * Provenance information + * EXP_NAME (string): Exposure name (e.g., "o1234g5678") + * EXP_ID (S64): Exposure identifier + * CHIP_ID (S64): Chip stage identifier + * CAM_ID (S64): Camera stage identifier + * FAKE_ID (S64): Fake stage identifier + * WARP_ID (S64): Warp stage identifier + * DIFF_ID (S64): Diff stage identifier + * DIFF_POS (boolean): Sense of subtraction; T for forward, F for backward + + * Exposure details + * MJD-OBS (F64): TAI MJD of exposure mid-point + * RA (string): Reported Right Ascension of telescope boresight, sexagesimal hours (e.g., "12:34:56.789") + * DEC (string): Reported Declination of telescope boresight, sexagesimal degrees (e.g., "-12:34:56.78") + * TEL_ALT (F64): Reported telescope altitude, degrees + * TEL_AZ (F64): Reported telescope azimuth, degrees + * EXPTIME (F32): Exposure time, seconds + * ROTANGLE (F64): Rotator angle, degrees + * FILTER (string): Filter name (e.g., "r.00000") + * AIRMASS (F32): Airmass for exposure + * OBSCODE (string): IAU observatory code (i.e., "F51" for PS1) + * SEEING (F32): Measured seeing at diff stage, arcsec + * MAGZP (F32): Magnitude zero point + * MAGZPERR (F32): Error in magnitude zero point + * ASTRORMS (F32): RMS of astrometric fit, arcsec + + * Detection efficiency + * DE_MAGnn (F32): Magnitude (calibrated) for detection efficiency + * DE_EFFnn (F32): Detection efficiency (0..1) + +==== Current limitations ==== + +The IPP is not yet calculating detection efficiencies (it is still +being developed). Further, it is not yet clear how to merge the +detection efficiency measurements for different skycells. Until these +issues are resolved, the detection efficiency values will be fake. + +==== Differences from original ICD ==== + + * SWSOURCE, SWVERSN has replaced TABLEVER which was never defined + * All of the "Provenance information" has replaced FPA_ID, for better tracking of the source of each detection + * SEEING and MAGZP added as indicators of the quality of the exposure + * MAGZPERR added to make absolute (i.e., across exposures) magnitude errors more accurate + * ASTRORMS added to make absolute (i.e., across exposures) astrometry errors more accurate + * DE_MAGnn and DE_EFFnn replace DE1 through DE10, which were never well defined + +=== Table === + +The table will contain information relevant to the individual +detections within the exposure. + + * RA (F64): Right Ascension of detection centre, degrees + * RA_ERR (F64): Error in RA, degrees + * DEC (F64): Declination of detection centre, degrees + * DEC_ERR (F64): Error in DEC, degrees + * MAG (F32): Calibrated magnitude of detection + * MAG_ERR (F32): Error in MAG + * STARPSF (F32): A PSF/extended source separator + * ANGLE (F64): Angle of trail fit to source, degrees E of N + * ANGLE_ERR (F64): Error in ANGLE, degrees + * LENGTH (F32): Length of trail fit to source, degrees + * LENGTH_ERR (F32): Error in LENGTH, degrees + * FLAGS (S32): IPP detection flags, bit mask + * DIFF_SKYFILE_ID (S64): IPP diff_skyfile_id for source + +==== Current limitations ==== + +The IPP is not yet fitting trails to sources in the difference images. +Until this is being done, the ANGLE, ANGLE_ERR, LENGTH and LENGTH_ERR +values will be zero. + +The value being written as STARPSF is EXT_NSIGMA from the IPP CMF +files; it is not clear that this is what MOPS wants, but this is +probably irrelevant until the trail fitting has been implemented. + +==== Differences from original ICD ==== + + * RA_DEG, DEC_DEG renamed RA, DEC to match apparent naming policy + * *_SIG renamed *_ERR to be more clear + * ANG, ANG_SIG, LEN, LEN_SIG spelled out as ANGLE, ANGLE_ERR, LENGTH, LENGTH_ERR + * FLUX, FLUX_SIG renamed MAG, MAG_ERR since IPP writes magnitudes + * FLAGS added to allow additional weeding out of bad detections + * DIFF_SKYFILE_ID added to allow trace back to IPP diff skyfile, for postage stamps + + + + + Table 3: IPP-MOPS Transient Detection Keywords +FITS Keyword Precision Description +FPA ID char(20) IPP-assigned identifier that can be used to trace back to this FPA +MJD-OBS F64 midpoint time of the exposure as a MJD and day fraction +RA HH:MM:SS.SSS field center RA at exposure midpoint, string +DEC sDD:MM:SS (s is + or -) field center declination at exposure midpoint, string +EXPTIME F64 exposure time in seconds +ROTANGLE F64 image rotation of the y-axis in degrees, from local N toward E +FILTER char(3) effective filter used for the exposure, one of g, r, i, z, y, B, V, w +AIRMASS F64 airmass at exposure midpoint +LIMITMAG F64 limiting magnitude of detections for this FPA +DE1 through DE10 F64 detection efficiency coefficients +OBSCODE char(5) MPC three-character observatory code +TEL ALT F64 telescope altitude at exposure midpoint, in degrees +TEL AZ F64 telescope azimuth at exposure midpoint, in degrees + Table 4: IPP-MOPS Transient Detection Table Columns + Column Precision Description + RA DEG F64 detection center coordinates in degrees + RA SIG F64 error in the detection center, in degrees + DEC DEG F64 detection center coordinates in degrees + DEC SIG F64 error in the detection center, in degrees + FLUX F64 flux + FLUX SIG F64 error in the flux value + STARPSF F64 probability that the PSF matches a starlike PSF + ANG F64 detection’s elongation angle in degrees, local N toward E + ANG SIG F64 error in the angle, in degrees + LEN F64 elongation length of the detection in degrees + LEN SIG F64 error in the length, in degrees