SIMPLE = T / file does conform to FITS standard BITPIX = 16 / number of bits per data pixel NAXIS = 2 / number of data axes NAXIS1 = 51 / length of data axis 1 NAXIS2 = 51 / length of data axis 2 EXTEND = T / FITS dataset may contain extensions COMMENT FITS (Flexible Image Transport System) format is defined in 'AstronomyCOMMENT and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H MESGNAME= 'XRT_IMAGE' / Name of the message TELESCOP= 'SWIFT ' / Telescope (mission) name INSTRUME= 'XRT ' / Instrument name OBS_ID = '01036227000' / Observation ID TARG_ID = '1036227 ' / Target ID SEG_NUM = '0 ' / Segment number CREATOR = 'TDRSS2FITS V3.21' / Program that created this FITS file ORIGIN = 'GSFC ' / Source of FITS file TLM2FITS= 'V3.21 ' / Telemetry converter version number EQUINOX = 2000 / Equinox RADECSYS= 'FK5 ' / Coordinates system TIMESYS = 'TT ' / Time system MJDREFI = 51910. / Reference MJD Integer part MJDREFF = 0.00074287037 / Reference MJD fractional TIMEUNIT= 's ' / Time unit for the time header keywords TIERRELA= 1.0E-08 / [s/s] Estimated relative clock rate error TIERABSO= 1. / [s] Estimated absolute clock offset error CLOCKAPP= F / If clock correction are applied (F/T) TIMEREF = 'LOCAL ' / Time reference (barycenter/local) TASSIGN = 'SATELLITE' / Time assigned by clock DATE = '2021-03-08T06:39:34' / file creation date (YYYY-MM-DDThh:mm:ss UT) TSTART = 636878388.446692 / Start time DATE-OBS= '2021-03-08T06:39:48.4' / Start Date TSTOP = 636878390.953992 / Stop time DATE-END= '2021-03-08T06:39:51.0' / Stop Date UTCFINIT= -26.63016 / UTCF at TSTART TRIGGER = 1036227 / Trigger Number FRAMENUM= 59867068 / CCD Frame Number HDUCLASS= 'OGIP ' / Format conforms to OGIP standards HDUCLAS1= 'IMAGE ' / Image data HDUCLAS2= 'TOTAL ' / Total data values DATAMODE= 'LONGIMA ' / XRT Mode for this data CTYPE1 = 'RAWX ' / WCS axis type CRPIX1 = 26 / WCS Reference point CDELT1 = 1 / WCS coordinate increment CUNIT1 = 'pixel ' / WCS axis unit CTYPE2 = 'RAWY ' / WCS axis type CRPIX2 = 26 / WCS Reference point CDELT2 = 1 / WCS coordinate increment CUNIT2 = 'pixel ' / WCS axis unit APID = 1250 / Application Process Identifier PACKET1 = T / Data from packet #1 present PACKET2 = T / Data from packet #2 present PACKET3 = T / Data from packet #3 present BLANK = -1 / Null data TELAPSE = 2.50729990005493 / TSTOP - TSTART ONTIME = 2.50729990005493 / Time on target LIVETIME= 2.50729990005493 / ONTIME multipled by DEADC EXPOSURE= 2.50729990005493 / Total exposure, with all known corrections DEADC = 1. / Dead time correction INVGAIN = 1 / Inverse gain (data were divided by this value) RAWXCTRD= 273.805419921875 / [pixel] GRB RAWX coordinates CenTRoiD RAWYCTRD= 269.713500976562 / [pixel] GRB RAWY coordinates CenTRoiD XRA_OBJ = 67.0767211914062 / [deg] XRT RA location of GRB or Object XDEC_OBJ= 37.4346694946289 / [deg] XRT DEC location of GRB or Object PA_PNT = 258.999084472656 / [deg] Roll angle from North towards East RAWXCEN = 274 / RAWX CENter image CRVAL1 = 274 / WCS reference value RAWYCEN = 270 / RAWY CENter image CRVAL2 = 270 / WCS reference value STDVCTRD= 8.2093563079834 / STandard DeViation of CenTRoiD MAXSTDV = 12. / MAX STandard DeViation of centroid EVTCTRD = 24 / no. of EVenTs in the CenTRoiD window MINEVENT= 20 / MInimum No. of EVenTs required for centroid P2ITER = 1 / Number of iterations for phase2 algorithm MAXITER = 4 / MAX ITERation for phase2 algorithm CONVDIST= 0. / actual CONVergence DISTance MAXCONV = 0.0625 / MAX CONVergence distance XRTMODE = 3 / XRT MODE for image WAVEFORM= 134 / XRT waveform P1UTCC = -26.63016 / [s] Packet #1 UTC Correction time P1UTCCS = -27 / Packet #1 UTC Correction Seconds P1UTCCSS= 18492 / [2*10**(-5) s] Packet #1 UTC Correction SubSecoPKT1TIME= 636878393.86146 / [s] ccsds PacKeT #1 TIME=PKT1SEC+PKT1SUBS*2e-5 PKT1SEC = 636878393 / ccsds PacKeT #1 SEConds PKT1SUBS= 43073 / [2*10**(-5) s] ccsds PacKeT #1 SUBSeconds CHECKSUM= 'eUXAfRV5eRVAeRV3' / HDU checksum updated 2021-03-08T06:39:44 DATASUM = '507780815' / data unit checksum updated 2021-03-08T06:39:44 FLUXFACT= 570000015360. / Flux conversion factor P2UTCC = -26.63016 / [s] Packet #2 UTC Correction time P2UTCCS = -27 / Packet #2 UTC Correction Seconds P2UTCCSS= 18492 / [2*10**(-5) s] Packet #2 UTC Correction SubSecoPKT2TIME= 636878394.06132 / [s] ccsds PacKeT #2 TIME=PKT2SEC+PKT2SUBS*2e-5 PKT2SEC = 636878394 / ccsds PacKeT #2 SEConds PKT2SUBS= 3066 / [2*10**(-5) s] ccsds PacKeT #2 SUBSeconds BOREROW = 298.100006103516 / BOREsight ROW in RAWY BORECOL = 291.600006103516 / BOREsight COLumn in RAWX BOREPA = 0. / [deg] BOREsight roll (Position Angle) PLATESCA= 2.3573100566864 / [arcsec/pixel] PLATE SCAle SCYCORR = 0. / [arcsec] Spacecraft to XRT Y boresight corr SCZCORR = 0. / [arcsec] Spacecraft to XRT Z boresight corr SCPACORR= 0. / [deg] Spacecraft to XRT roll boresight corr TAMREFX1= 327.640014648438 / TAM Ref Window 1 X pos TAMREFY1= 237.199996948242 / TAM Ref Window 1 Y pos TAMREFX2= 261.324005126953 / TAM Ref Window 2 X pos TAMREFY2= 242. / TAM Ref Window 2 Y pos TAMTHETA= 17. / TAM THETA-t angle XRT-PSU-037 TAMOPTGN= 1.00999999046326 / TAM OPTical GaiN XRT-LUX-TN-095 TAMPRIPS= 9.49600028991699 / TAM PRImary window Plate Scale TAMSECPS= 5.65999984741211 / TAM SECondary window Plate Scale TAMSEQCN= 489728 / TAM image SEQuence CouNt TAMCTRDC= T / TAM CenTRoiD Calculated? TAMCORR = F / TAM CORRection enabled? NOMEXPO = 2.50729990005493 / [s] NOMinal EXPOsure for flux calculation RA_PNT = 67.1083831787109 / [deg] Spacecraft RA DEC_PNT = 37.4206275939941 / [deg] Spacecraft Dec GRBYXRT = -66.9157638549805 / GRB Y in XRT Coords GRBZXRT = -79.1928634643555 / GRB Z in XRT Coords XHIGHRA = 67.0767243681495 / [deg] XRT HIGH precision GRB RA (double) XHIGHDEC= 37.4346704002077 / [deg] XRT HIGH precision GRB DEC (double) WINHALFW= 25 / WINdow HALF Width MINSTDV = 5 / MIN STandard DeViation of centroid TLMVER = 3 / Telemetry version from packet #3 P3UTCC = -26.63016 / [s] Packet #3 UTC Correction time P3UTCCS = -27 / Packet #3 UTC Correction Seconds P3UTCCSS= 18492 / [2*10**(-5) s] Packet #3 UTC Correction SubSecoPKT3TIME= 636878394.26186 / [s] ccsds PacKeT #3 TIME=PKT3SEC+PKT3SUBS*2e-5 PKT3SEC = 636878394 / ccsds PacKeT #3 SEConds PKT3SUBS= 13093 / [2*10**(-5) s] ccsds PacKeT #3 SUBSeconds END   $0 F  ='+-  6