| 9 | | Magnitudes are AB magnitudes (flux zero point is 3631 Jy). |
| 10 | | |
| 11 | | Unless otherwise noted, error values are statistical only, and include |
| 12 | | no contribution by systematic errors. |
| 13 | | |
| 14 | | == Primary header == |
| 15 | | |
| 16 | | The primary header will not contain any information beyond that |
| 17 | | written automatically by cfitsio, and is present only for compliance |
| 18 | | with the FITS standard. |
| 19 | | |
| 20 | | == FITS table == |
| 21 | | |
| 22 | | The FITS table will include all detections within an exposure. |
| 23 | | |
| 24 | | Duplicates from overlapping skycells will have been filtered out by |
| 25 | | IPP, with the measurements from the source closest to the centre of a |
| 26 | | skycell included (and all others discarded). |
| 27 | | |
| 28 | | === Header === |
| 29 | | |
| 30 | | The header will contain information relevant to the exposure as a whole. |
| 31 | | |
| 32 | | * Version information |
| 33 | | * SWSOURCE (string): source of software (e.g., "60eb6cdc-a59c-4636-a4e0-dba66a9721fd") |
| 34 | | * SWVERSN (string): version of software (e.g., "trunk/ppMops@24658") |
| 35 | | |
| 36 | | * Provenance information |
| 37 | | * EXP_NAME (string): Exposure name (e.g., "o1234g5678") |
| 38 | | * EXP_ID (S64): Exposure identifier |
| 39 | | * CHIP_ID (S64): Chip stage identifier |
| 40 | | * CAM_ID (S64): Camera stage identifier |
| 41 | | * FAKE_ID (S64): Fake stage identifier |
| 42 | | * WARP_ID (S64): Warp stage identifier |
| 43 | | * DIFF_ID (S64): Diff stage identifier |
| 44 | | * DIFF_POS (boolean): Sense of subtraction; T for forward, F for backward |
| 45 | | |
| 46 | | * Exposure details |
| 47 | | * MJD-OBS (F64): TAI MJD of exposure mid-point |
| 48 | | * RA (string): Reported Right Ascension of telescope boresight, sexagesimal hours (e.g., "12:34:56.789") |
| 49 | | * DEC (string): Reported Declination of telescope boresight, sexagesimal degrees (e.g., "-12:34:56.78") |
| 50 | | * TEL_ALT (F64): Reported telescope altitude, degrees |
| 51 | | * TEL_AZ (F64): Reported telescope azimuth, degrees |
| 52 | | * EXPTIME (F32): Exposure time, seconds |
| 53 | | * ROTANGLE (F64): Rotator angle, degrees |
| 54 | | * FILTER (string): Filter name (e.g., "r.00000") |
| 55 | | * AIRMASS (F32): Airmass for exposure |
| 56 | | * OBSCODE (string): IAU observatory code (i.e., "F51" for PS1) |
| 57 | | * SEEING (F32): Measured seeing at diff stage, arcsec |
| 58 | | * MAGZP (F32): Magnitude zero point |
| 59 | | * MAGZPERR (F32): Error in magnitude zero point |
| 60 | | * ASTRORMS (F32): RMS of astrometric fit, arcsec |
| 61 | | |
| 62 | | * Detection efficiency |
| 63 | | * DE_MAGnn (F32): Magnitude (calibrated) for detection efficiency |
| 64 | | * DE_EFFnn (F32): Detection efficiency (0..1) |
| 65 | | |
| 66 | | ==== Current limitations ==== |
| 67 | | |
| 68 | | The IPP is not yet calculating detection efficiencies (it is still |
| 69 | | being developed). Further, it is not yet clear how to merge the |
| 70 | | detection efficiency measurements for different skycells. Until these |
| 71 | | issues are resolved, the detection efficiency values will be fake. |
| 72 | | |
| 73 | | ==== Differences from original ICD ==== |
| 74 | | |
| 75 | | * SWSOURCE, SWVERSN has replaced TABLEVER which was never defined |
| 76 | | * All of the "Provenance information" has replaced FPA_ID, for better tracking of the source of each detection |
| 77 | | * SEEING and MAGZP added as indicators of the quality of the exposure |
| 78 | | * MAGZPERR added to make absolute (i.e., across exposures) magnitude errors more accurate |
| 79 | | * ASTRORMS added to make absolute (i.e., across exposures) astrometry errors more accurate |
| 80 | | * DE_MAGnn and DE_EFFnn replace DE1 through DE10, which were never well defined |
| 81 | | * Removed LIMITMAG, which was never well defined, and is unnecessary given the DE_MAGnn and DE_EFFnn |
| 82 | | |
| 83 | | === Table === |
| 84 | | |
| 85 | | The table will contain information relevant to the individual |
| 86 | | detections within the exposure. |
| 87 | | |
| 88 | | * RA (F64): Right Ascension of detection centre, degrees |
| 89 | | * RA_ERR (F64): Error in RA, degrees |
| 90 | | * DEC (F64): Declination of detection centre, degrees |
| 91 | | * DEC_ERR (F64): Error in DEC, degrees |
| 92 | | * MAG (F32): Calibrated magnitude of detection |
| 93 | | * MAG_ERR (F32): Error in MAG |
| 94 | | * PSF_CHI2 (F32): chi^2^ of PSF fit |
| 95 | | * PSF_DOF (S32): Degrees of freedom of PSF fit |
| 96 | | * CR_SIGNIFICANCE (F32): Significance of CR |
| 97 | | * EXT_SIGNIFICANCE (F32): Significance of extendedness |
| 98 | | * PSF_MAJOR (F32): PSF major axis (pixels) |
| 99 | | * PSF_MINOR (F32): PSF minor axis (pixels) |
| 100 | | * PSF_THETA (F32): PSF position angle (deg on chip) |
| 101 | | * PSF_QUALITY (F32): PSF quality factor |
| 102 | | * PSF_NPIX (S32): Number of pixels in PSF |
| 103 | | * MOMENTS_XX (F32): xx moment |
| 104 | | * MOMENTS_XY (F32): xy moment |
| 105 | | * MOMENTS_YY (F32): yy moment |
| 106 | | * N_POS (S32): Number of positive pixels |
| 107 | | * F_POS (F32): Fraction of positive pixels |
| 108 | | * RATIO_BAD (F32): Ratio of positive pixels to negative |
| 109 | | * RATIO_MASK (F32): Ratio of positive pixels to masked |
| 110 | | * RATIO_ALL (F32): Ratio of positive pixels to all |
| 111 | | * FLAGS (S32): IPP detection flags, bit mask |
| 112 | | * DIFF_SKYFILE_ID (S64): IPP diff_skyfile_id for source |
| 113 | | |
| 114 | | ==== Current limitations ==== |
| 115 | | |
| 116 | | The IPP is not yet fitting trails to sources in the difference images. |
| 117 | | Until this is being done, the ANGLE, ANGLE_ERR, LENGTH and LENGTH_ERR |
| 118 | | values will be zero. |
| 119 | | |
| 120 | | The value being written as STARPSF is EXT_NSIGMA from the IPP CMF |
| 121 | | files; it is not clear that this is what MOPS wants, but this is |
| 122 | | probably irrelevant until the trail fitting has been implemented. |
| 123 | | |
| 124 | | ==== Differences from original ICD ==== |
| 125 | | |
| 126 | | * RA_DEG, DEC_DEG renamed RA, DEC to match apparent naming policy |
| 127 | | * *_SIG renamed *_ERR to be more clear |
| 128 | | * ANG, ANG_SIG, LEN, LEN_SIG removed; these can be calculated from the moments |
| 129 | | * FLUX, FLUX_SIG renamed MAG, MAG_ERR since IPP writes magnitudes |
| 130 | | * FLAGS added to allow additional weeding out of bad detections |
| 131 | | * DIFF_SKYFILE_ID added to allow trace back to IPP diff skyfile, for postage stamps |
| 132 | | * STARPSF renamed EXT_SIGNIFICANCE to be more clear |
| 133 | | * Added PSF_CHI2, PSF_DOF, CR_SIGNIFICANCE, PSF_MAJOR, PSF_MINOR, PSF_THETA, PSF_QUALITY, PSF_NPIX, MOMENTS_XX, MOMENTS_XY, MOMENTS_YY for more complete data on each detection |
| 134 | | * Added N_POS, F_POS, RATIO_BAD, RATIO_MASK, RATIO_ALL for better weeding out of bad subtractions |
| 135 | | |
| 136 | | === Example === |
| 137 | | |
| 138 | | {{{ |
| 139 | | XTENSION= 'BINTABLE' / binary table extension |
| 140 | | BITPIX = 8 / 8-bit bytes |
| 141 | | NAXIS = 2 / 2-dimensional binary table |
| 142 | | NAXIS1 = 120 / width of table in bytes |
| 143 | | NAXIS2 = 42032 / number of rows in table |
| 144 | | PCOUNT = 0 / size of special data area |
| 145 | | GCOUNT = 1 / one data group (required keyword) |
| 146 | | TFIELDS = 25 / number of fields in each row |
| 147 | | TTYPE1 = 'RA ' / label for field 1 |
| 148 | | TFORM1 = '1D ' / data format of field: 8-byte DOUBLE |
| 149 | | TTYPE2 = 'RA_ERR ' / label for field 2 |
| 150 | | TFORM2 = '1D ' / data format of field: 8-byte DOUBLE |
| 151 | | TTYPE3 = 'DEC ' / label for field 3 |
| 152 | | TFORM3 = '1D ' / data format of field: 8-byte DOUBLE |
| 153 | | TTYPE4 = 'DEC_ERR ' / label for field 4 |
| 154 | | TFORM4 = '1D ' / data format of field: 8-byte DOUBLE |
| 155 | | TTYPE5 = 'MAG ' / label for field 5 |
| 156 | | TFORM5 = '1E ' / data format of field: 4-byte REAL |
| 157 | | TTYPE6 = 'MAG_ERR ' / label for field 6 |
| 158 | | TFORM6 = '1E ' / data format of field: 4-byte REAL |
| 159 | | TTYPE7 = 'PSF_CHI2' / label for field 7 |
| 160 | | TFORM7 = '1E ' / data format of field: 4-byte REAL |
| 161 | | TTYPE8 = 'PSF_DOF ' / label for field 8 |
| 162 | | TFORM8 = '1J ' / data format of field: 4-byte INTEGER |
| 163 | | TTYPE9 = 'CR_SIGNIFICANCE' / label for field 9 |
| 164 | | TFORM9 = '1E ' / data format of field: 4-byte REAL |
| 165 | | TTYPE10 = 'EXT_SIGNIFICANCE' / label for field 10 |
| 166 | | TFORM10 = '1E ' / data format of field: 4-byte REAL |
| 167 | | TTYPE11 = 'PSF_MAJOR' / label for field 11 |
| 168 | | TFORM11 = '1E ' / data format of field: 4-byte REAL |
| 169 | | TTYPE12 = 'PSF_MINOR' / label for field 12 |
| 170 | | TFORM12 = '1E ' / data format of field: 4-byte REAL |
| 171 | | TTYPE13 = 'PSF_THETA' / label for field 13 |
| 172 | | TFORM13 = '1E ' / data format of field: 4-byte REAL |
| 173 | | TTYPE14 = 'PSF_QUALITY' / label for field 14 |
| 174 | | TFORM14 = '1E ' / data format of field: 4-byte REAL |
| 175 | | TTYPE15 = 'PSF_NPIX' / label for field 15 |
| 176 | | TFORM15 = '1J ' / data format of field: 4-byte INTEGER |
| 177 | | TTYPE16 = 'MOMENTS_XX' / label for field 16 |
| 178 | | TFORM16 = '1E ' / data format of field: 4-byte REAL |
| 179 | | TTYPE17 = 'MOMENTS_XY' / label for field 17 |
| 180 | | TFORM17 = '1E ' / data format of field: 4-byte REAL |
| 181 | | TTYPE18 = 'MOMENTS_YY' / label for field 18 |
| 182 | | TFORM18 = '1E ' / data format of field: 4-byte REAL |
| 183 | | TTYPE19 = 'N_POS ' / label for field 19 |
| 184 | | TFORM19 = '1J ' / data format of field: 4-byte INTEGER |
| 185 | | TTYPE20 = 'F_POS ' / label for field 20 |
| 186 | | TFORM20 = '1E ' / data format of field: 4-byte REAL |
| 187 | | TTYPE21 = 'RATIO_BAD' / label for field 21 |
| 188 | | TFORM21 = '1E ' / data format of field: 4-byte REAL |
| 189 | | TTYPE22 = 'RATIO_MASK' / label for field 22 |
| 190 | | TFORM22 = '1E ' / data format of field: 4-byte REAL |
| 191 | | TTYPE23 = 'RATIO_ALL' / label for field 23 |
| 192 | | TFORM23 = '1E ' / data format of field: 4-byte REAL |
| 193 | | TTYPE24 = 'FLAGS ' / label for field 24 |
| 194 | | TFORM24 = '1J ' / data format of field: 4-byte INTEGER |
| 195 | | TZERO24 = 2147483648 / offset for unsigned integers |
| 196 | | TSCAL24 = 1 / data are not scaled |
| 197 | | TTYPE25 = 'DIFF_SKYFILE_ID' / label for field 25 |
| 198 | | TFORM25 = '1K ' / data format of field: 8-byte INTEGER |
| 199 | | SWSOURCE= '60eb6cdc-a59c-4636-a4e0-dba66a9721fd' / Software source |
| 200 | | SWVERSN = 'branches/pap_mops/ppMops@25227' / Software version |
| 201 | | HISTORY ppMops at 2009-09-02T03:48:46.695783 |
| 202 | | HISTORY psLib version: branches/pap_mops/psLib@25227 |
| 203 | | HISTORY psLib source: 60eb6cdc-a59c-4636-a4e0-dba66a9721fd |
| 204 | | HISTORY ppMops version: branches/pap_mops/ppMops@25227 |
| 205 | | HISTORY ppMops source: 60eb6cdc-a59c-4636-a4e0-dba66a9721fd |
| 206 | | EXP_NAME= 'o4995g0129o' / Exposure name |
| 207 | | EXP_ID = 77164 / Exposure identifier |
| 208 | | CHIP_ID = 24019 / Chip stage identifier |
| 209 | | CAM_ID = 17726 / Cam stage identifier |
| 210 | | FAKE_ID = 10227 / Fake stage identifier |
| 211 | | WARP_ID = 8842 / Warp stage identifier |
| 212 | | DIFF_ID = 19219 / Diff stage identifier |
| 213 | | DIFF_POS= F / Positive subtraction? |
| 214 | | MJD-OBS = 54995.4740598313 / MJD of exposure midpoint |
| 215 | | RA = '18:25:01.988' / Right Ascension of boresight |
| 216 | | DEC = '-17:20:40.069' / Declination of boresight |
| 217 | | TEL_ALT = 51.951873 / Telescope altitude |
| 218 | | TEL_AZ = 179.483883 / Telescope azimuth |
| 219 | | EXPTIME = 38. / Exposure time (sec) |
| 220 | | ROTANGLE= 333.1039 / Rotator position angle |
| 221 | | FILTER = 'r.00000 ' / Filter name |
| 222 | | AIRMASS = 1.269 / Airmass of exposure |
| 223 | | OBSCODE = 'F51 ' / IAU Observatory code |
| 224 | | SEEING = 1.678401 / Mean seeing |
| 225 | | MAGZP = 28.65226 / Magnitude zero point |
| 226 | | MAGZPERR= 0.353063 / Error in magnitude zero point |
| 227 | | ASTRORMS= 0.3111496 / RMS of astrometric fit |
| 228 | | EXTNAME = 'MOPS_TRANSIENT_DETECTIONS' |
| 229 | | END |
| 230 | | }}} |
