Astrosat Project Level2 Interface Control Document Level2 Data Pipeline Software for Soft X-Ray Telescope (SXT)

Home , Astrosat

Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017 Astrosat Project Level2 Interface Control Document Level2 Data Pipeline Software For Soft X-ray Telescope (SXT)

SAC DP Team Navita Thakkar, P. Neethi Nathan, Arvind K Singh, T. P. Srinivasan, B. Gopala Krishna

Instrument Team Prof. Sudip Bhattacharyya, Ms.Nilima Kamble, S. L. Vishwakarma, J G Koyande September 2017

High Resolution Data Processing Division Satellite Photogrammetry and Digital Cartography Group Signal and Image Processing Area Space Applications Centre Ahmedabad-380015

1 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

Space Applications Centre (ISRO), Ahmedabad Document Control and Data Sheet

1 Report No & : Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept. Date 2016 2 Title : Astrosat Project- Level2 Interface Control Document Level2 data pipeline software for Soft X-ray Telescope(SXT)

3 Version : 1.3

4 No. of Pages : 48

5 No. of : 4 References

6 Authors : SAC DP Team – Navita Thakkar, Neethi Nathan, Arvind K. Singh, T. P. Srinivasan, B. Gopala Krishna

Instrument Team – Prof. Sudip Bhattacharyya, Nilima Kamble, S.L. Vishwakarma, J G Koyande

7 Originating : High Resolution Data Processing Division, Unit Satellite Photogrammetry and Digital Cartography Group,Signal and Image Processing Area

8 Abstract : This document describes the level2 output data formats to be generated from Level-2 data pipeline software.

9 Keywords : Astrosat, SXT, MKF, FITS, PHAS, PI

10 Security : Restricted Classification

2 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

Astrosat Project- Level2 Interface Control Document Level-2 data pipeline software for Soft X-ray Telescope (SXT) Document Change History *A: Addition; M: Modification; D: Deletion

Version Date Section A/M/D Description of change No. No. * V 1.0 Aug. 2012 All A Initial Version

V 1.1 Sep. 2016 All M Changed version V 1.2 Nov. 2016 2 M Changed version V 1.3 Sep. 2017 1 & 2 M Changed version

3 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

Table of Contents

DOCUMENT CONTROL AND DATA SHEET...... ……..…..2 ASTROSAT PROJECT - LEVEL 2 INTERFACE CONTROL DOCUMENT …………………..…...2 LEVEL -2 DATA PIPELINE SOFTWARE FOR SOFT X- RAY TELESCOPE (SXT)...... ……....2 DOCUMENT CHANGE HISTORY …………………………………...... …….... 3 1. INTRODUCTION...... …….. 5 2. LEVEL2 DATA ORGANISATION...... ……...... …. 6 3. LEVEL2 OUTPUT DATA FORMATS...... ……...... 6 3.1 LEVEL2 EVENT FILE 3.1.1 PRIMARY HEADER FITS...... …………………..7 3.1.2 EVENTS HEADER FITS FORMAT...... …….…..8 3.1.3 GTI HEADER FITS FORMAT...... …….………..10 3.1.4 BADPIX HEADER FITS FORMAT...... ………...12 3.2 CLEAN EVENT FILE 3.2.1 PRIMARY HEADER FITS FORMAT...... ……....13 3.2.2 EVENTS HEADER FITS FORMAT ...... 15 3.2.3 GTI HEADER FITS FORMAT ...... ………...17 3.2.4 BADPIX H EADER FITS FORMAT ...... ………….19 3.3 LIGHT CURVE FILE 3.3.1 Primary Header FITS FORMAT...... ……….20 3.3.2 RATE Header FITS FORMAT…...... 21 3.3.3 GTI Header FITS FORMAT…...... 23 3.3.4 REG00101 HEADER FITS format …...... …….24 3.4 SPECTRUM FILE 3.4.1 PRIMARY HEADER FITS FORMAT...... 25 3.4.2 SPECTRUM HEADER FITS FORMAT...... 29 3.4.3 GTI HEADER FITS FORMAT...... 31 3.4.4 REG00101 HEADER FITS FORMAT 3.5 IMAGE FILE 3.5.1 PRIMARY HEADER FITS FORMAT...... 34

3.6 TCT FILE

3.6.1 PRIMARY HEADER FITS FORMAT...... 35 3.6.2 TCT HEADER FITS FORMAT...... 36

3.7 MKF FILE

3.7.1 PRIMARY HEADER FITS FORMAT...... 38 3.7.2 MKF HEADER FITS FORMAT...... 39

3.8 LBT HK FILE

3.8.1 PRIMARY HEADER FITS FORMAT …...... 40 3.8.2 LBT HK HEADER FITS FORMAT...... 45 3.9 ATTITUDE FILE

3.9.1 PRIMARY HEADER FITS FORMAT...... 46 3.9.2 ATTITUDE HEADER FITS FORMAT...... 47

4.REFERENCES...... 48

4 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

1.Introduction The Level2 ICD contains Level2 output data files format for the Soft X-ray Telescope (SXT) of Astrosat. All the outputs files will be in FITS Format. The Level2 Output data files are provided for each OBS ID. Under each OBS ID there are multiple tar files. Each tar file named as ( LEVL2AS1SXTyyyymmdd__OrbNo.tar_VerNo ) corresponds to one data dump orbit as received from ISSDC as level-1.

 Level2 Event File (.evt)  Level2 Clean Event File (_cl.evt)  Image File (.img)  Spectrum File (.pha)  Light Curve File (.lc)  Region text file (.reg)  Xselect commands text file (.xco)  Level2 Pipeline Log File  Data quality report text file(_DQR.txt) The Other ancillary files are inherited from the Level1 are  Time Calibration Table (.tct) Data File  Make Filter Data File (.mkf)  Low Bit rate House Keeping file (.lbt)  Attitude File (.att)

2.Level2 Data Organisation Organized level-2 data set comes in tar format as ( LEVL2AS1SXTyyyymmdd__OrbNo.tar_VerNo ) and after extracting the directory structure for data organization after level2 processing is given below. The files under yyyymmdd__level2_OrbNo_VerNo directory will be generated during level2 data processing and other files viz. lbt file, attitude file, orbit file, mkf file will be copied from level1 to level2 directory. File names will bear the data mode and mode's status bits, MM and WW respectively.

5 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017 yyyymmdd__level2_OrbNo_VerNo/sxt/OrbNo/ AS1sxt_level2.mkf sxt.01/ cs_pha/ (15 files) cs_pi/ (15 files) AS1sxtMMWW_level2.evt AS1sxtMMWW_level2_cl.evt AS1sxtMMWW_level2.img AS1sxtMMWW_level2.pha AS1sxtMMWW_level2.lc AS1sxtMMWW_level2_region.reg AS1sxtMMWW_level2_br_earth_remove.xco AS1sxtMMWW_level2_ci_sxtproducts.xco AS1sxtMMWW_level2_sxtscreen.xco aux/AS1sxt_level2.tct aux1/AS1sxt_level2.att aux2/AS1sxt_level2.lbt yyyymmdd__level2_OrbNo_VerNo/ yyyymmdd_yyyymmdd_ObsID_level2_OrbNo_VerNo (Pipeline log file ) yyyymmdd_ObsID_level2_OrbNo_VerNo_DQR.txt (DQR text file)

6 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

3.Level2 output data formats The detailed format description for all the Level2 data files are described in detail in respective sections which shown below.

3.1 Level2 Event File AS1sxtMMWW_level2.evt Where OBSID is Observation ID, MM is the Data Mode, WW mode's status bits.

3.1.1 Primary Header FITS format SIMPLE = T / File does not conform to FITS standard BITPIX = 8 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may include extensions MISSION = 'ASTROSAT' / Mission Name ORIGIN = 'NASA/GSFC' / Origin of fits file CREATOR = 'extractor v5.25' / Extractor TELESCOP = 'ASTROSAT' / Telescope (mission) name INSTRUME = 'SXT ' / Instrument name DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) DATE-OBS = / Start date of observation DATE-END = / End date of observation TIME-OBS = / Start time of observation TIME-END = / End time of observation TIMESYS = 'UTC ' / Time measured from MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) = / MJD = JD - 2400000.5 TIMEZERI = / Clock correction integer TIMEZERF = / Clock correction fractional TIMEDEL = / Time resolution TIMEUNIT = 's ' / Unit for time keywords TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTOPI = / integer observation stop time TSTOPF = / fractional observation stop time OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA pointing DEC_PNT = / [deg] Nominal DEC pointing EQUINOX = 2000.0 / Equinox of celestial coord system RADECSYS = 'ICRS ' / Celestial coord system OBSERVER = / Observation information block OBS_ID = / Observation Id SOURCEID = / Source Id TARGETID = / Target Id EXP_TIME = / Exposure Time ORB_NUM = nnnnn / Orbit Number CHECKSUM = / HDU checksum updated yyyy-mm-ddThh:mm:ss 7 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

USER = / User name of creator TOTAL2K = / Total Number of Two Packets analyzed ERROR2K = / Total Number of Two Packets with Error DATASUM = / Data unit checksum updated yyyy-mm- ddThh:mm:ss NEVENTS = / Number of events DATAMODE = / Data mode ONTIME = / On-source time EXPOSURE = / Exposure time LIVE TIME = / On-source time TSTART = / Time start TSTOP = / Time stop TELAPSE = / Elapsed time MJD-OBS = / MJD of data start time TIME REF = / Reference time FILIN001 = / Input file name TIMEZERO = / Time zero END

3.1.2 EVENTS Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 57 / width of table in bytes NAXIS2 = 33595 / number of rows in table PCOUNT = 0 / size of special data area: GCOUNT = 1 / one data group (required keyword) TFIELDS = 15 / number of fields in each row ORIGIN = 'NASA/GSFC' / Origin of fits file CREATOR = 'extractor v5.25 / Extractor TELESCOP = 'ASTROSAT' / Telescope (mission) name INSTRUME = 'SXT' / Instrument name OBS_ID = / Observation ID SOURCEID = / Source ID TARGETID = / Target ID DATAMODE = / Datamode OBS_MODE = / Observation Mode EXTNAME = / Name OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA Pointing DEC_PNT = / [deg] Nominal DEC Pointing RA_NOM = / [deg] Nominal Average RA Pointing DEC_NOM = / [deg] Nominal Average DEC Pointing DATE-OBS = / Start date of observation DATE-END = / End date of observation TIME-OBS = / Start time of observation TIME-END = / End time of observation MJDREFI = / MJD Reference day MJDREFF = / MJD Reference (fraction of day) = / MJD=JD – 2400000.5 8 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TASSIGN = 'SATELLITE' / Time assigned by clock (INSTRUMENT/SATELLITE) = / (INSTRUMENT = OBT_TIME) (SATELLITE = SPS_TIME) TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords TSTART = / time start TSTOP = / time stop TIMEDEL = / Time Resolution EXP_TIME = / Exposure Time EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system

TTYPE1 = 'TIME’ / Time of events TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 's’ / physical unit of field

TTYPE2 = 'CCDFrame' / CCD FRAME number TFORM2 = '1J’ / data format of field: 4-byte INTEGER TUNIT2 = / Physical unit of field

TTYPE3 = 'X’ / Event X position Sky coordinates TFORM3 = '1I’ / data format of field : 2-byte INTEGER TUNIT3 = 'pixel’ / physical unit of field TLMIN3 = 1 / Minimum value for X column TLMAX3 = 1000 / Maximum value for X column STATUS

TTYPE4 = 'Y’ / Event Y position Sky coordinates TFORM4 = '1I’ / data format of field: 2-byte INTEGER TUNIT4 = 'pixel’ / physical unit of field TLMIN4 = 1 / Minimum value for Y column TLMAX4 = 1000 / Maximum value for Y column

TTYPE5 = 'RAWX’ / Event X position RAW coordinates TFORM5 = '1I’ / data format of field TUNIT5 = 'pixel’ / physical unit of field TLMIN5 = 0 / minimum value for RAWX column TLMAX5 = 599 / maximum value for RAWX column

TTYPE6 = 'RAWY’ / Event Y position RAW coordinates TFORM6 = '1I’ / data format of field: 2-byte INTEGER TUNIT6 = 'pixel’ / physical unit of field TLMIN6 = 0 / Minimum value for RAWY column TLMAX6 = 599 / maximum value for RAWY column

TTYPE7 = 'DETX’ / Event X position DET coordinates TFORM7 = '1I’ / data format of field: 2-byte INTEGER TUNIT7 = 'pixel’ / physical unit of field TLMIN7 = 1 / Minimum value for DETX column TLMAX7 = 600 / Maximum value for DETX column

TTYPE8 = 'DETY’ / Event Y position DET coordinates TFORM8 = '1I’ / data format of field: 2-byte INTEGER 9 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TUNIT8 = 'pixel’ / physical unit of field TLMIN8 = 1 / Minimum value for DETY column TLMAX8 = 600 / Maximum value for DETY column

TTYPE9 = 'PHAS’ / Array of Pulse Height Analyzer values TFORM9 = '9I’ / data format of field: 2-byte INTEGER TUNIT9 = 'channel’ / physical unit of field TTYPE10 = 'STATUS’ / Label for field TFORM10 = '16X’ / format of field

TTYPE11 = 'PHA’ / Label for field TFORM11 = '1J’ / format of field TLMIN11 = 32 / Minimum value for PHA column TLMAX11 = 35091 / Maximum value for PHA column

TTYPE12 = 'GRADE’ / Label for field TFORM12 = '1I’ / format of field TLMIN12 = 0 / minimum value for GRADE column TLMAX12 = 32 / Maximum value for GRADE column

TTYPE13 = 'PI’ / Label for field TFORM13 = '1I’ / format of field

TTYPE14 = 'PI' / Label for field TFORM14 = '1J’ / format of field TUNIT14 = channel / physical unit of field TLMIN14 = 10 / Minimum value for PI column TLMAX14 = 9842 / Maximum value for PI column = / WHALFWD = 300 / Window Half Width WHALFHT = 300 / Window Half Height = / TCTYPE3 = RA---TAN / X coordinate type TCRPX3 = / X image reference pixel TCRVL3 = / X image reference pixel coordinate (deg) TCDLT3 = / X image scale (deg/pixel) TCUNI3 = / X units TNULL3 = / X null value

TCTYP4 = / Y coordinate type TCRPX4 = / Y image reference pixel TCRVL4 = / Y image reference pixel coordinate (deg) TCDLT4 = / Y image scale (deg/pixel) TCUNI4 = deg / Y units TNULL4 = / Y null value

TCTYP5 = RAWX / WCS axis type TCRVL5 = / WCS reference value TCDLT5 = / WCS coordinate increment TCRPX5 = / WCS Reference point

10 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TCTYP6 = / WCS axis type TCRVL6 = / WCS reference value TCDLT6 = / WCS coordinate increment TCRPX6 = / WCS Reference point

TCTYP7 = / DETX coordinate type TCRPX7 = / DETX image reference pixel TCRVL7 = / DETX image reference pixel coordinate (mm) TCDLT7 = / DETX image scale (mm/pixel) TCUNI7 = mm / DETX units

TCTYP8 = DETY / DETY coordinate type TCRPX8 = / DETY image reference pixel TCRVL8 = / DETY image reference pixel coordinate (mm) TCDLT8 = / DETY image scale (mm/pixel) TCUNI8 = mm / DETY units

CHECKSUM = / HDU checksum updated 2016-10-03T07:15:48 DATASUM = / data unit checksum updated 2016-10- 03T07:15:48 USER = / User name of creator XM_COORD = / Lower Left CCD Window X-Coordinate YM_COORD = / Lower Left CCD Window Y-Coordinate XN_COORD = / Upper Right CCD Window X-Coordinate YN_COORD = / Upper Right CCD Window Y-Coordinate ORB_NUM = /

TIMEZERO = / Time Zero ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time TELAPSE = / elapsed time MJD-OBS = / MJD of data start time TIMEREF = / reference time FILIN001 = / Input file name DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) NPIXSOU = / Number of pixels in selected region TTYPE15 = / label for field TFORM15 = / Format of field AVG_BIAS = / Average Bias Value BIAS_SUB = / BIAS Subtracted END =

11 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

3.1.3 GTI Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 57 / width of table in bytes NAXIS2 = 33595 / number of rows in table PCOUNT = 0 / size of special data area: GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row

TTYPE1 = 'START ’ / label for field 1 TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 's’ / physical unit of field

TTYPE2 = STOP / label for field 2 TFORM2 = '1D’ / data format of field: 8-byte DOUBLE TUNIT2 = s / Physical unit of field

EXTNAME GTI ' name of this binary table extension HDUCLASS OGIP File conforms to OGIP/GSFC conventions HDUCLAS1 GTI File contains Good Time Intervals HDUCLAS2 STANDARD File contains Good Time Intervals TELESCOP = 'ASTROSAT' / Telescope (mission) name DATAMODE = / Datamode INSTRUME = 'SXT' / Instrument name OBJECT = / Name of observed object ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time DATE-OBS = / Start date of observation DATE-END = / End date of observation TIME-OBS = / Start time of observation TIME-END = / End time of observation TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time TIMEREF = / reference time TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system USER = / User name of creator FILIN001 = / Input file name CREATOR = 'extractor v5.25 / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 'NASA/GSFC' / Origin of fits file 12 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

HDUNAME GTI ASCDM block name MTYPE1 TIME Data type MFORM1 START,STOP names of the start and stop columns METYP1 R data descriptor type: Range, binned data CHECKSUM HDU checksum updated 2016-10-03T07:15:31 DATASUM data unit checksum updated 2016-10-03T07:15:31 END

3.1.4 BADPIX Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 57 / width of table in bytes NAXIS2 = 33595 / number of rows in table PCOUNT = 0 / size of special data area: GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row

TTYPE1 = RAWX / label for field 1 TFORM1 = '1I’ / data format of field: 2-byte INTEGER

TTYPE2 = RAWY / label for field 2 TFORM2 = '1I’ / data format of field: 2-byte INTEGER TUNIT2 = s / Physical unit of field

TTYPE3 = 'TYPE’ / label for field 3 TFORM3 = '1I’ / data format of field : 2-byte INTEGER

TTYPE4 = YEXTENT / label for field 4 TFORM4 = '1I’ / data format of field: 2-byte INTEGER

TTYPE5 = BADFLAG / label for field 5 TFORM5 = '16X’ / data format of field: BIT

EXTNAME BADPIX name of this binary table extension CHECKSUM HDU checksum updated 2016-10-03T07:15:31 DATASUM data unit checksum updated 2016-10-03T07:15:31 END

3.2 Clean Event File AS1sxtMMWW_level2_cl.evt Where OBSID is observation ID, MM is the Mode, WW mode status bits.

3.2.1 Primary Header FITS format SIMPLE = T / file does conform to FITS standard BITPIX = 8 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may include extensions MISSION = 'ASTROSAT' / Mission Name 13 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

ORIGIN = 'SXTPOC@TIFR' / origin of fits file CREATOR = 'extractor v5.25 ' / Extractor TELESCOP = 'ASTROSAT' / Telescope (mission) name INSTRUME = 'SXT ' / Instrument name DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) DATE-OBS = / Start date of observations DATE-END = / End date of observations TIME-OBS = / Start time of observations TIME-END = / End time of observations

TIMESYS = 'UTC ' / time measured from MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) = / MJD = JD - 2400000.5 TIMEZERI = / Clock correction integer TIMEZERF = / Clock correction fractional TIMEDEL = / Time resolution TIMEUNIT = 's ' / unit for time keywords TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTOPI = / integer observation stop time TSTOPF = / fractional observation stop time OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA pointing DEC_PNT = / [deg] Nominal DEC pointing EQUINOX = / Equinox of celestial coord system RADECSYS = 'ICRF ' / celestial coord system OBSERVER = / Observation information block OBS_ID = / Observation Id SOURCEID = / Source Id TARGETID = / Target Id EXP_TIME = / Exposure Time ORB_NUM = nnnnn / Orbit Number CHECKSUM = / HDU checksum updated 2016-10-03T07:15:51 USER = / User name of creator TOTAL2K = / Total Number of Two Packets analyzed ERROR2K = / Total Number of Two Packets with Error DATASUM = / data unit checksum updated 2016-10- 03T07:15:29 NEVENTS = / Number of events DATAMODE = / Datamode ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time 14 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

MJD-OBS = / MJD of data start time TIMEREF = / reference tiCyg X-2 me FILIN001 = / Input file name TIMEZERO = / Time Zero MEDIAN = / Average (Median) Count Rate MEAN = / Average(Mean) Count Rate END = /

3.2.2 EVENTS Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 57 / width of table in bytes NAXIS2 = 33595 / Number of events PCOUNT = 0 / size of special data area: GCOUNT = 1 / one data group (required keyword) TFIELDS = 15 / number of fields in each row ORIGIN = SXTPOC@TIFR / origin of FITS file CREATOR = extractor v5.25 / Extractor TELESCOP = ASTROSAT / Telescope (mission) name INSTRUME = SXT / Instrument name OBS_ID = / Observation ID SOURCEID Source ID TARG_ID = / Target ID DATAMODE = / Datamode OBS_MODE = / Observation Mode EXTNAME = ‘EVENTS’ / Name OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA Pointing DEC_PNT = / [deg] Nominal DEC Pointing RA_NOM = / [deg] Nominal Average RA Pointing DEC_NOM = / [deg] Nominal Average DEC Pointing DATE-OBS = / Start date of observation DATE-END = / End date of observation TIME-OBS = / Start time of observation TIME-END = / End time of observation MJDREFI = / MJD Reference day MJDREFF = / MJD Reference (fraction of day) = / MJD=JD – 2400000.5 TASSIGN = 'SATELLITE' / Time assigned by clock (INSTRUMENT/SATELLITE) = / (INSTRUMENT = OBT_TIME) (SATELLITE = SPS_TIME) TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords TSTART = / time start TSTOP = / time stop TIMEDEL = / Time Resolution EXP_TIME = / Exposure Time EQUINOX = / Equinox of celestial coord system

15 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

RADECSYS = ICRS / celestial coord system

TTYPE1 = 'TIME’ / Time of events TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 'seconds ’ / physical unit of field

TTYPE2 = 'CCDFrame' / CCD FRAME number TFORM2 = '1J’ / data format of field: 4-byte INTEGER TUNIT2 physical unit of field

TTYPE3 = 'X’ / Event X position Sky coordinates TFORM3 = '1I’ / data format of field: 2-byte INTEGER TUNIT3 = 'pixel’ / physical unit of field TLMIN3 = 1 / Minimum value for X column TLMAX3 = 1000 / Maximum value for X column

TTYPE5 = 'RAWX’ / Event X position RAW coordinates TFORM5 = '1I’ / data format of field: 2-byte INTEGER TUNIT5 = 'pixel’ / physical unit of field TLMIN5 = 0 / Minimum value for RAWX column TLMAX5 = 599 / Maximum value for RAWX column

TTYPE8 = 'DETY’ / Event Y position DET coordinates TFORM8 = '1I’ / data format of field: 2-byte INTEGER TUNIT8 = 'pixel’ / physical unit of field TLMIN8 = 1 / Minimum value for DETY column TLMAX8 = 600 / Maximum value for DETY column

TTYPE9 = 'PHAS’ / Array of Pulse Height Analyzer values TFORM9 = '9I’ / data format of field: 2-byte INTEGER TUNIT9 = 'channel’ / physical unit of field TLMIN9 = 0 / minimum legal value in the column TLMAX9 = 4095 / maximum legal value in the column

TTYPE10 = 'STATUS ’ / label for field TFORM10 = '1B’ / format of field

16 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TTYPE11 = 'PHA’ / Label for field TFORM11 = '1J’ / format of field TLMIN11 = 0 / Minimum value for PHA column TLMAX11 = 4095 / Maximum value for PHA column

TTYPE12 = 'GRADE ’ / label for field TFORM12 = '1J’ / format of field TLMIN12 = / Minimum value for GRADE column TLMAX12 = / Maximum value for GRADE column

TTYPE13 = 'PixsAbove’ / label for field TFORM13 = '1I’ / format of field 1.0000000000E +06

TTYPE14 = 'PI' / label for field TFORM14 = '1J’ / format of field TUNIT14 channel physical unit of field TLMIN14 0 Minimum value for PI column TLMAX14 1023 Maximum value for PI column

WHALFWD = 300 / Window Half Width WHALFHT = 300 / Window Half Height = / TCTYPE3 = RA---TAN / X coordinate type TCRPX3 = / X image reference pixel TCRVL3 = / X image reference pixel coordinate (deg) TCDLT3 = / X image scale (deg/pixel) TCUNI3 = / X units TNULL3 = / X null value

TCTYP4 = / Y coordinate type TCRPX4 = / Y image reference pixel TCRVL4 = / Y image reference pixel coordinate (deg) TCDLT4 = / Y image scale (deg/pixel) TCUNI4 = deg / Y units TNULL4 = / Y null value

TCTYP5 = RAWX / WCS axis type TCRVL5 = / WCS reference value TCDLT5 = / WCS coordinate increment TCRPX5 = / WCS Reference point

TCTYP6 = RAWY / WCS axis type TCRVL6 = / WCS reference value TCDLT6 = / WCS coordinate increment TCRPX6 = / WCS Reference point

TCTYP7 = DETX / DETX coordinate type 17 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TCRPX7 = / DETX image reference pixel TCRVL7 = / DETX image reference pixel coordinate (mm) TCDLT7 = / DETX image scale (mm/pixel) TCUNI7 = mm / DETX units

TCTYP8 = DETY / DETY coordinate type TCRPX8 = / DETY image reference pixel TCRVL8 = / DETY image reference pixel coordinate (mm) TCDLT8 = / DETY image scale (mm/pixel) TCUNI8 = mm / DETY units

TIMEZERO Time Zero ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time TELAPSE = / elapsed time MJD-OBS = / MJD of data start time TIMEREF = / reference tiCyg X-2 me FILIN001 = / Input file name DATE file creation date (YYYY-MM-DDThh:mm:ss UT) NPIXSOU = / Number of pixels in selected region TTYPE15 = / label for field TFORM15 = / Format of field AVG_BIAS = / Average Bias Value BIAS_SUB = / BIAS Subtracted END

3.2.3 GTI Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 57 / width of table in bytes NAXIS2 = 33595 / number of rows in table PCOUNT = 0 / size of special data area: GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row

18 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TTYPE1 = 'START ’ / label for field 1 TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 's’ / physical unit of field

TTYPE2 = STOP / label for field 2 TFORM2 = '1D’ / data format of field: 8-byte DOUBLE TUNIT2 = s / Physical unit of field

EXTNAME GTI ' name of this binary table extension HDUCLASS OGIP File conforms to OGIP/GSFC conventions HDUCLAS1 GTI File contains Good Time Intervals HDUCLAS2 STANDARD File contains Good Time Intervals TELESCOP = 'ASTROSAT' / Telescope (mission) name DATAMODE = / Datamode INSTRUME = 'SXT' / Instrument name OBJECT = / Name of observed object ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time DATE-OBS = / Start date of observation DATE-END = / End date of observation TIME-OBS = / Start time of observation TIME-END = / End time of observation TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time MJDREFI = / MJD Reference day MJDREFF = / MJD Reference (fraction of day) TIMEREF = / reference time TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system USER = / User name of creator FILIN001 = / Input file name CREATOR = 'extractor v5.25 / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 'NASA/GSFC' / Origin of fits file HDUNAME GTI ASCDM block name MTYPE1 TIME Data type MFORM1 START,STOP names of the start and stop columns METYP1 R data descriptor type: Range, binned data CHECKSUM HDU checksum updated 2016-10-03T07:15:31 DATASUM data unit checksum updated 2016-10-03T07:15:31 END

3.2.4 BADPIX Header FITS format XTENSION = 'BINTABLE' / binary table extension

19 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 57 / width of table in bytes NAXIS2 = 33595 / number of rows in table PCOUNT = 0 / size of special data area: GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row

TTYPE1 = RAWX / label for field 1 TFORM1 = '1I’ / data format of field: 2-byte INTEGER

TTYPE2 = RAWY / label for field 2 TFORM2 = '1I’ / data format of field: 2-byte INTEGER TUNIT2 = s / Physical unit of field

TTYPE3 = 'TYPE’ / label for field 3 TFORM3 = '1I’ / data format of field : 2-byte INTEGER

TTYPE4 = YEXTENT / label for field 4 TFORM4 = '1I’ / data format of field: 2-byte INTEGER

TTYPE5 = BADFLAG / label for field 5 TFORM5 = '16X’ / data format of field: BIT

EXTNAME BADPIX name of this binary table extension CHECKSUM HDU checksum updated 2016-10-03T07:15:31 DATASUM data unit checksum updated 2016-10-03T07:15:31 ORIGIN 'SXTPOC@TIFR' END

3.3 Light Curve File AS1sxtMMWW_level2.lc Where OBSID is observation ID, MM is the Mode, WW is mode status bit.

3.3.1 Primary Header FITS format SIMPLE = T / HDU 0 BITPIX = 8 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may include extensions COMMENT FITS (Flexible Image Transport System) format is defined in 'Astronomy COMMENT and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H TELESCOP = 'ASTROSAT' / Telescope (mission) name DATAMODE = Datamode

20 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

INSTRUME = 'SXT ' / Instrument name OBJECT = / Name of observed object ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time DATE-OBS = / Start date of observations TIME-OBS = / Start time of observations DATE-END = / End date of observations TIME-END = / End time of observations TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) TIMEREF = / reference time TIMESYS = 'UTC ' / time measured from TIMEUNIT = / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system USER = 'sxtpoc ' / User name of creator FILIN001 = / Input file name CREATOR = / Extractor version DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 's ' / origin of fits file TIMEDEL = / Binning factor CHECKSUM = / HDU checksum updated 2016-10-03T07:15:54 DATASUM = / data unit checksum updated 2016-10- 03T07:15:54 END /

3.3.2 RATE Header FITS format XTENSION = 'BINTABLE' / Binary table Extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 20 / width of table in bytes NAXIS2 = / Number of bins PCOUNT = 0 / size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 4 / number of fields in each row TTYPE1 = 'TIME ' / label for field 1 TFORM1 = '0 ' / data format of field: 8-byte DOUBLE TUNIT1 = 's ' / physical unit of field TTYPE2 = 'RATE ' / label for field 2 TFORM2 = 'E' / data format of field: 4-byte REAL TUNIT2 = 'count/s ' / physical unit of field

21 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TTYPE3 = 'E' / label for field 3 TFORM3 = / data format of field: 4-byte REAL TUNIT3 = / physical unit of field TTYPE4 = / label for field 4 TFORM4 = 'E' / data format of field: 4-byte REAL EXTNAME = 'RATE' / name of this binary table extension ORIGIN = 'NASA/GSFC' / origin of fits file CREATOR = 'extractor v5.25' / Extractor TELESCOP = 'ASTROSAT' / Telescope (mission) name INSTRUME = / Instrument name OBS_ID = / Observation ID SOURCEID = / Source ID TARGETID = / Target ID DATAMODE = / Datamode OBS_MODE = / Observation Mode OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA pointing DEC_PNT = / [deg] Nominal DEC pointing RA_NOM = / [deg] Nominal Average RA pointing DEC_NOM = / [deg] Nominal Average DEC pointing DATE-OBS = / Start date of observations DATE-END = / End date of observations TIME-OBS = / Start time of observations TIME-END = / End time of observations MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) / MJD = JD - 2400000.5 TASSIGN = / Time assigned by clock (INSTRUMENT/SATELLITE) (INSTRUMENT = OBT_TIME) (SATELLITE = SPS_TIME) TIMESYS = / time measured from TIMEUNIT = / unit for time keywords TSTART = / time start TSTOP = / time stop TIMEDEL = / Binning factor EXP_TIME = / Exposure Time EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system WHALFWD = / Window Half Width WHALFHT = / Window Half Height USER = / User name of creator XM_COORD = / Lower Left CCD Window X-Coordinate YM_COORD = / Lower Left CCD Window Y-Coordinate XN_COORD = / Upper Right CCD Window X-Coordinate YN_COORD = / Upper Right CCD Window Y-Coordinate ORB_NUM = /

22 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time TELAPSE = / elapsed time MJD-OBS = / MJD of data start time TIMEREF = / reference time FILIN001 = / Input file name DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) NPIXSOU = / Numbers of Pixels AVG_BIAS = / Average Bias Value BIAS_SUB = / BIAS Subtracted DSTYP1 = / Data subspace descriptor: name DSREF1 = / Data subspace descriptor: reference DSVAL1 = / Data subspace descriptor: value HDUCLASS = / Format conforms to OGIP/GSFC conventions HDUCLAS1 = / Extension contains a light curve HDUCLAS2 = 'TOTAL ' / HDUCLAS3 = 'RATE ' / TIMEPIXR = / Timestamps give center of bin PHALCUT = / Minimum PI channel PHAHCUT = / Maximum PI channel MINFREXP = / Minimum value of FRACEXP included CHECKSUM = / HDU checksum updated 2016-10-03T07:15:54 DATASUM = / data unit checksum updated 2016-10-03T07:15:54 MEDIAN = / Average(Median) Count Rate MEAN = / Average(Mean) Count Rate END

3.3.3 GTI Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 16 / width of table in bytes NAXIS2 = 3 / number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row

TTYPE1 = 'START ’ / label for field 1 TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 's’ / physical unit of field

TTYPE2 = 'STOP ' / label for field 2 TFORM2 = '1D’ / data format of field: 8-byte DOUBLE TUNIT2 = 's ' / Physical unit of field

23 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

EXTNAME 'GTI ' name of this binary table extension HDUCLASS 'OGIP ' File conforms to OGIP/GSFC conventions HDUCLAS1 'GTI ' File contains Good Time Intervals HDUCLAS2 'STANDARD' File contains Good Time Intervals TELESCOP = 'ASTROSAT' / Telescope (mission) name DATAMODE = / Datamode INSTRUME = 'SXT' / Instrument name OBJECT = / Name of observed object ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time DATE-OBS = / Start date of observation TIME-OBS Start time of observation DATE-END = / End date of observation TIME-END = / End time of observation TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) TIMEREF = / reference time TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system USER = / User name of creator FILIN001 = / Input file name CREATOR = 'extractor v5.25 / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 'NASA/GSFC' / Origin of fits file HDUNAME 'GTI ' ASCDM block name MTYPE1 'TIME ' Data type MFORM1 'START,STOP' names of the start and stop columns METYP1 'R ' data descriptor type: Range, binned data CHECKSUM HDU checksum updated 2016-10-03T07:15:54 DATASUM data unit checksum updated 2016-10-03T07:15:54 END

3.3.4 REG00101 Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 50 / width of table in bytes NAXIS2 = 1 / number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 6 / number of fields in each row

24 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TTYPE1 = 'RAWX ' / label for field 1 TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 'pixel ' / physical unit of field

TTYPE2 = 'RAWY ' / CCD FRAME number TFORM2 = '1D’ / data format of field: 8-byte DOUBLE TUNIT2 = 'pixel ' / Physical unit of field

TTYPE3 = 'SHAPE ' / label for field 3 TFORM3 = '16A’ / data format of field: ASCII Character

TTYPE4 = 'R ' / label for field 4 TFORM4 = '1D ’ / data format of field: 8-byte DOUBLE TUNIT4 = 'pixel’ / physical unit of field

TTYPE5 = 'ROTANG ' / label for field 5 TFORM5 = '1D ’ / data format of field: 8-byte DOUBLE TUNIT5 = 'degree ' / physical unit of field

TTYPE6 = 'COMPONENT' / label for field 6 TFORM6 = '1I’ / data format of field: 2-byte INTEGER

EXTNAME = 'REG00101' / name of this binary table extension EXTVER = 1 / Level i DB hierarchy: Data table EXTLEVEL = 1 / HDUNAME = 'REGION ' / ASCDM block name HDUCLASS = 'ASC ' / Region extension HDUCLAS1 = 'REGION ' / Region extension HDUCLAS2 = 'STANDARD' / Region extension HDUVERS = '1.0.0 ' / HDUDOC = 'ASC-FITS- / REGION-1.0: McDowell, Rots: FITS REGION Binary Table Design' CONTENT = 'REGION ' / CXC Content Key TELESCOP = 'ASTROSAT' / Telescope (mission) name DATAMODE = / Datamode INSTRUME = 'SXT ' / Instrument name OBJECT = / Name of observed object ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time DATE-OBS = / Start date of observations TIME-OBS = / Start time of observations DATE-END = / End date of observations TIME-END = / End time of observations TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time 25 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) TIMEREF = ' ' / reference time TIMESYS = 'UTC ' / time measured from TIMEUNIT = 's ' / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = 'ICRS ' / celestial coord system USER = 'sxtpoc ' / User name of creator FILIN001 = / Input file name CREATOR = / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 'NASA/GSFC' / origin of fits file MTYPE1 = 'pos ' / DM Keyword: Descriptor name. MFORM1 = 'RAWX,RAWY' / DM Keyword: Descriptor value. TCTYP1 = 'RAWX ' / TCRPX1 = / X axis reference pixel TDRPX1 = / original X axis reference pixel TCRVL1 = / Coord of X ref pixel TCDLT1 = / X axis increment TDDLT1 = / original X axis increment TCTYP2 = 'RAWY ' / projection TCRPX2 = / Y axis reference pixel TDRPX2 = / original Y axis reference pixel TCRVL2 = / Coord of Y ref pixel TCDLT2 = / Y axis increment TDDLT2 = / original Y axis increment TCROT2 / Sky coord rotation angle CHECKSUM = / HDU checksum updated 2016-10-03T07:15:52 DATASUM = / data unit checksum updated 2016-10- 03T07:15:52 END =

3.4 Spectrum File AS1sxtMMWW_level2.pha Where OBSID is observation ID, MM is the Mode, WW is mode status bit.

3.4.1 Primery Header FITS form SIMPLE = T / HDU 0 BITPIX = 8 / Number of bits per data pixel NAXIS = 0 / Number of data axes NAXIS1 / length of data axis 1 NAXIS2 / length of data axis 2 EXTEND = T / FITS dataset may contain extensions MISSION = 'ASTROSAT' / Mission Name ORIGIN = 'NASA/GSFC' / origin of fits file CREATOR = 'extractor v5.25' / Extractor 26 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TELESCOP = 'ASTROSAT' / Telescope (mission) name INSTRUME = 'SXT ' / Instrument name DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) DATE-OBS = / Start date of observations DATE-END = / End date of observations TIME-OBS = / Start time of observations TIME-END = / End time of observations TIMESYS = 'UTC ' / T time measured from MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) = / MJD = JD - 2400000.5 TIMEZERI = / Clock correction integer TIMEZERF = / Clock correction fractional TIMEDEL = / Time resolution TIMEUNIT = 's ' / unit for time keywords TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTOPI = / integer observation stop time TSTOPF = / Name of observed object OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA pointing DEC_PNT = / [deg] Nominal DEC pointing EQUINOX = / Equinox of celestial coord system RADECSYS = 'ICRS ' / celestial coord system OBSERVER = / Observation information block OBS_ID = / Observation Id SOURCEID = / Source Id TARGETID = / Target Id EXP_TIME = / Exposure Time ORB_NUM = / Orbit Number USER = / User name of creator TOTAL2K = / Total Number of Two Packets analyzed ERROR2K = / Total Number of Two Packets with Error DATAMODE = / Datamode ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time TIMEREF = / reference time FILIN001 = / Input file name TIMEZERO = / Time Zero OBS_MODE = / Observation Mode RA_NOM = / [deg] Nominal Average RA pointing DEC_NOM = / [deg] Nominal Average DEC pointing TASSIGN = / Time assigned by clock 27 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

(INSTRUMENT/SATELLITE) WHALFWD = / Window Half Width WHALFHT = / Window Half Height XM_COORD = / Lower Left CCD Window X-Coordinate YM_COORD = / Lower Left CCD Window Y-Coordinate XN_COORD = / Upper Right CCD Window X-Coordinate YN_COORD = / Upper Right CCD Window Y-Coordinate AVG_BIAS = / Average Bias Value BIAS_SUB = / BIAS Subtracted DSTYP1 = / Data subspace descriptor: name DSREF1 = / Data subspace descriptor: reference DSVAL1 = / Data subspace descriptor: value HDUNAME = 'WMAP ' / HDUCLASS = / Format conforms to OGIP/GSFC conventions HDUCLAS1 = / Extension contains an image HDUCLAS2 = / Extension contains a weighted map AXLEN1 = / Dim of axis 1 AXLEN1 = / Dim of axis 1 AXLEN2 = / Dim of axis 2 CONTENT = / spectrum file contains time intervals and event WMREBIN = / Weighted Map rebinning OBS-MODE = / observing mode 1=point,2=slew,3=calibration SKYBIN = / Image binning factor PIXSIZE = / Image binsize (degrees) WMAPFIX = / If true pixels outside selected region set to - CTYPE1 = 'RA---TAN' / CRPIX1 = / X axis reference pixel DRPIX1 = / original X axis reference pixel CRVAL1 = / coord of X ref pixel CDELT1 = / X axis increment DDELT1 = / original X axis increment CTYPE2 = 'DEC--TAN' / CRPIX2 = / Y axis reference pixel DRPIX2 = / original Y axis reference pixel CRVAL2 = / coord of Y ref pixel CDELT2 = / Y axis increment DDELT2 = / original Y axis increment WCSNAMEP = 'PHYSICAL' / WCSTY1P = 'PHYSICAL' / LTV1 = / offset for logical to physical pixel LTM1_1 = / slope for logical to physical pixel CTYPE1P = / Source of X-axis CRPIX1P = / X axis reference pixel CRVAL1P = / coord of X ref pixel in original image CDELT1P = / X axis increment WCSTY2P = 'PHYSICAL' / LTV2 = / offset for logical to physical pixel LTM2_2 = / slope for logical to physical pixel 28 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

CTYPE2P = / Source of Y-axis CRPIX2P = / Y axis reference pixel CRVAL2P = / coord of Y ref pixel in original image CDELT2P = / Y axis increment HDUVERS = / Version of format (OGIP memo OGIP-96-001) OPTIC1 = / X Optical axis OPTIC2 = / Y Optical axis BBOX1 = / extractor bbox(1) BBOX2 = / extractor bbox(2) HBBOX1 = / extractor hbbox(1) HBBOX2 = / extractor hbbox(2) X-OFFSET = / first original X pixel in map Y-OFFSET = / first original Y pixel in map TOTCTS = / Total pixel count REFXCTYP = / projection REFXCRPX = / Original X axis reference pixel REFXCRVL = / Original Coord of X ref pixel REFXCDLT = / Original X axis increment REFYCTYP = / projection REFYCRPX = / Original Y axis reference pixel REFYCRVL = / Original Coord of Y ref pixel REFYCDLT = / Original Y axis increment CHECKSUM = / HDU checksum updated 2016-10-03T07:15:54 DATASUM = / data unit checksum updated 2016-10-03T07:15:54 END

3.4.2 SPECTRUM Header FITS format XTENSION = 'BINTABLE' / Binary table Extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2 dimensional binary axis NAXIS1 = / width of table in bytes NAXIS2 = / number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row TTYPE1 = / Pulse Invarient (PI) Channel TFORM1 = 'J' / data format of field: 4-byte INTEGER TTYPE2 = 'COUNTS' / Counts per channel TFORM2 = 'J' / data format of field: 4-byte INTEGER TUNIT2 = / physical unit of field EXTNAME = 'SPECTRUM' / name of this binary table extension HDUCLASS = 'OGIP' / format conforms to OGIP standard HDUCLAS1 = 'SPECTRUM' / PHA dataset (OGIP memo OGIP-92-007) HDUVERS1 = / Obsolete - included for backwards compatibility HDUVERS = / Version of format (OGIP memo OGIP-92-007) HDUCLAS2 = / Gross PHA Spectrum (source + bkgd) HDUCLAS3 = / PHA data stored as Counts (not count/s) TLMIN1 = / Lowest legal channel number

29 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TLMAX1 = / Highest legal channel number TELESCOP = / Telescope (mission) name INSTRUME = 'SXT ' / Instrument name FILTER = 'NONE ' / no filter in use EXPOSURE = / Exposure time AREASCAL = / area scaling factor BACKFILE = / associated background filename BACKSCAL = / background file scaling factor CORRFILE = / associated correction filename CORRSCAL = / correction file scaling factor RESPFILE = / associated redistrib matrix filename RESPFILE = / associated redistrib matrix filename ANCRFILE = / associated ancillary response filename PHAVERSN = / obsolete DETCHANS = / total number possible channels CHANTYPE = / channel type (PHA, PI etc) POISSERR = / Poissonian errors to be assumed STAT_ERR = / no statistical error specified SYS_ERR = / no systematic error specified GROUPING = / no grouping of the data has been defined QUALITY = / no data quality information specified DATAMODE = / Datamode OBJECT = / Name of observed object ONTIME = / On-source time LIVETIME = / On-source time DATE-OBS = / Start date of observations TIME-OBS = / Start time of observations DATE-END = / End date of observations TIME-END = / End time of observations TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) TIMEREF = / reference time TIMESYS = / time measured from TIMEUNIT = / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = / celestial coord system USER = / User name of creator FILIN001 = / Input file name CREATOR = / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = / origin of fits file TOTCTS = / Total counts in spectrum RA_PNT = / File average of RA(degrees) 30 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

DEC_PNT = / File average of DEC(degrees) SPECDELT = / Binning factor for spectrum SPECPIX = / The rebinned channel corresponding to SPECVAL SPECVAL = / Original channel value at center of SPECPIX DSTYP1 = / Data subspace descriptor: name DSVAL1 = / Data subspace descriptor: value DSREF1 = / Data subspace descriptor: reference CHECKSUM = / HDU checksum updated 2016-10-03T07:15:54 DATASUM = / data unit checksum updated 2016-10- 03T07:15:54 END

3.4.3 GTI Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 16 / width of table in bytes NAXIS2 = 3 / number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 2 / number of fields in each row

TTYPE1 = 'START ’ / label for field 1 TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 's’ / physical unit of field

TTYPE2 = 'STOP ' / label for field 2 TFORM2 = '1D’ / data format of field: 8-byte DOUBLE TUNIT2 = 's ' / Physical unit of field

TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) TIMEREF = / reference time TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = 'ICRS ' / celestial coord system USER = 'sxtpoc ' / User name of creator FILIN001 = / Input file name CREATOR = 'extractor v5.25 / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 'NASA/GSFC' / Origin of fits file HDUNAME 'GTI ' ASCDM block name MTYPE1 'TIME ' Data type MFORM1 'START,STOP' names of the start and stop columns METYP1 'R ' data descriptor type: Range, binned data CHECKSUM HDU checksum updated 2016-10-03T07:15:54 DATASUM data unit checksum updated 2016-10-03T07:15:54 END

3.4.4 REG00101 Header FITS format XTENSION = 'BINTABLE' / binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional binary table NAXIS1 = 50 / width of table in bytes NAXIS2 = 1 / number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 6 / number of fields in each row

TTYPE1 = 'RAWX ' / label for field 1 TFORM1 = '1D’ / data format of field: 8-byte DOUBLE TUNIT1 = 'pixel ' / physical unit of field

TTYPE2 = 'RAWY ' / CCD FRAME number TFORM2 = '1D’ / data format of field: 8-byte DOUBLE TUNIT2 = 'pixel ' / Physical unit of field

TTYPE3 = 'SHAPE ' / label for field 3 TFORM3 = '16A’ / data format of field: ASCII Character

TTYPE4 = 'R ' / label for field 4 TFORM4 = '1D ’ / data format of field: 8-byte DOUBLE TUNIT4 = 'pixel’ / physical unit of field

TTYPE5 = 'ROTANG ' / label for field 5 32 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TFORM5 = '1D ’ / data format of field: 8-byte DOUBLE TUNIT5 = 'degree ' / physical unit of field

TTYPE6 = 'COMPONENT' / label for field 6 TFORM6 = '1I’ / data format of field: 2-byte INTEGER

EXTNAME = 'REG00101' / name of this binary table extension EXTVER = 1 / EXTLEVEL = 1 / Level i DB hierarchy: Data table HDUNAME = 'REGION ' / ASCDM block name HDUCLASS = 'ASC ' / Region extension HDUCLAS1 = 'REGION ' / Region extension HDUCLAS2 = 'STANDARD' / Region extension HDUVERS = '1.0.0 ' / HDUDOC = 'ASC-FITS- / REGION-1.0: McDowell, Rots: FITS REGION Binary Table Design' CONTENT = 'REGION ' / CXC Content Key TELESCOP = 'ASTROSAT' / Telescope (mission) name DATAMODE = / Datamode INSTRUME = 'SXT ' / Instrument name OBJECT = / Name of observed object ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time DATE-OBS = / Start date of observations TIME-OBS = / Start time of observations DATE-END = / End date of observations TIME-END = / End time of observations TSTART = / time start TSTOP = / time stop TELAPSE = / elapsed time MJD-OBS = / MJD of data start time MJDREFI = / MJD reference day MJDREFF = / MJD reference (fraction of day) TIMEREF = ' ' / reference time TIMESYS = 'UTC ' / time measured from TIMEUNIT = 's ' / unit for time keywords EQUINOX = / Equinox of celestial coord system RADECSYS = 'ICRS ' / celestial coord system USER = 'sxtpoc ' / User name of creator FILIN001 = / Input file name CREATOR = / Extractor DATE = / file creation date (YYYY-MM-DDThh:mm:ss UT) ORIGIN = 'NASA/GSFC' / origin of fits file MTYPE1 = 'pos ' / DM Keyword: Descriptor name. MFORM1 = 'RAWX,RAWY' / DM Keyword: Descriptor value. TCTYP1 = 'RAWX ' / 33 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TCRPX1 = / X axis reference pixel TDRPX1 = / original X axis reference pixel TCRVL1 = / Coord of X ref pixel TCDLT1 = / X axis increment TDDLT1 = / original X axis increment TCTYP2 = 'RAWY ' / projection TCRPX2 = / Y axis reference pixel TDRPX2 = / original Y axis reference pixel TCRVL2 = / Coord of Y ref pixel TCDLT2 = / Y axis increment TDDLT2 = / original Y axis increment TCROT2 / Sky coord rotation angle CHECKSUM = / HDU checksum updated 2016-10-03T07:15:52 DATASUM = / data unit checksum updated 2016-10- 03T07:15:52 END =

3.5 Image File AS1sxtMMWW_level2.img Where OBSID is observation ID, MM is the Mode, WW is the mode status bit.

3.5.1 Primary Header FITS format SIMPLE = T / file does conform to FITS standard BITPIX = 8 / Number of Bits per data pixel NAXIS = 2 / Number of data axis NAXIS1 = 1000 / length of data axis 1 NAXIS2 = 1000 / length of data axis 2 EXTEND = T / FITS data sets may include extension ORIGIN = ‘NASA/GSFC’ / origin of fits file CREATOR = extractor v5.25 / Extractor TELESCOP = ASTROSAT / Telescope (mission) name INSTRUME = SXT / Instrument name OBS_ID = / Observation ID SOURCEID Source ID TARGETID = / Target ID DATAMODE = / Datamode OBS_MODE = / Observation Mode OBJECT = / Name of observed object RA_PNT = / [deg] Nominal RA Pointing DEC_PNT = / [deg] Nominal DEC Pointing RA_NOM = / [deg] Nominal Average RA Pointing DEC_NOM = / [deg] Nominal Average DEC Pointing DATE-OBS = / Start date of observation DATE-END = / End date of observation TIME-OBS = / Start time of observation TIME-END = / End time of observation 34 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

MJDREFI = / MJD Reference day MJDREFF = / MJD Reference (fraction of day) = / MJD=JD – 2400000.5 TASSIGN = 'SATELLITE' / Time assigned by clock (INSTRUMENT/SATELLITE) = / (INSTRUMENT = OBT_TIME) (SATELLITE = SPS_TIME) TIMESYS = 'UTC’ / time measured from TIMEUNIT = 's’ / unit for time keywords TSTART = / time start TSTOP = / time stop TIMEDEL = / Time Resolution EXP_TIME = / Exposure Time EQUINOX = / Equinox of celestial coord system RADECSYS = ICRS / celestial coord system WHALFWD = 300 / Window Half Width WHALFHT = 300 / Window Half Height USER = / User name of creator XM_COORD = / Lower Left CCD Window X-Coordinate YM_COORD = / Lower Left CCD Window Y-Coordinate XN_COORD = / Upper Right CCD Window X-Coordinate YN_COORD = / Upper Right CCD Window Y-Coordinate ORB_NUM = /

TIMEZERO = Time Zero ONTIME = / On-source time EXPOSURE = / Exposure time LIVETIME = / On-source time TELAPSE = / elapsed time MJD-OBS = / MJD of data start time TIMEREF = / reference tiCyg X-2 me FILIN001 = / Input file name DATE file creation date (YYYY-MM-DDThh:mm:ss UT) NPIXSOU = / Number of pixels in selected region AVG_BIAS = / Average Bias Value BIAS_SUB = / BIAS Subtracted DSTYP1 = 'POS(RAWX,RAW / Data subspace descriptor: name Y)' DSREF1 = ':REG00101' / Data subspace descriptor: reference DSVAL1 = 'TABLE ' / Data subspace descriptor: value CONTENT = 'IMAGE ' / image file HDUNAME = 'IMAGE ' / HDUCLASS = 'ogip ' / Format conforms to OGIP/GSFC conventions HDUCLAS1 = 'IMAGE ' / Extension contains an image DROLLANG = / Mean roll angle (deci. deg) IMGBIN = / Image binning factor CTYPE1 = 'RA---TAN' / CRPIX1 = / X axis reference pixel DRPIX1 = / original X axis reference pixel 35 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

CRVAL1 = / Coord of X ref pixel CDELT1 = / X axis increment DDELT1 = / original X axis increment CTYPE2 = / projection CRPIX2 = / Y axis reference pixel DRPIX2 = / original Y axis reference pixel CRVAL2 = / Coord of Y ref pixel CDELT2 = / Y axis increment DDELT2 = / original Y axis increment CROTA2 = / Sky coord rotation angle WCSNAMEP = / 'PHYSICAL' WCSTY1P = / 'PHYSICAL' LTV1 = / offset for logical to physical pixel LTM1_1 = / slope for logical to physical pixel CTYPE1P = ASTROSAT-SXT-L1/ Source of X-axis CRPIX1P = / X axis reference pixel CRVAL1P = / coord of X ref pixel in original image CDELT1P = / X axis increment WCSTY2P = 'PHYSICAL' / LTV2 = / offset for logical to physical pixel LTM2_2 = / slope for logical to physical pixel CTYPE2P = / Source of Y-axis CRPIX2P = / Y axis reference pixel CRVAL2P = / coord of Y ref pixel in original image CDELT2P = / Y axis increment TOTCTS = / Total pixel count CHANMIN = / Low PI channel CHANMAX = / High PI channel CHANTYPE = / Energy channel name CHECKSUM = / HDU checksum updated 2016-10-03T07:15:54 DATASUM = / data unit checksum updated 2016-10-03T07:15:54 END = /

3.6 TCT FILE AS1sxt_level2.tct Where OBSID is observation ID, MM is the Mode, WW is the mode status bit.

3.6.1 Primary Header FITS format SIMPLE = T / file does conform to FITS standard BITPIX = 16 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may contain extensions 36 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

ORIGIN = 'ASTROSAT-SXT-L2' / Configuration control CREATOR = 'SXT-L1 ' / program name that created file TELESCOP = 'ASTROSAT ' / telescope name DATE = / file creation date DATE-OBS = / Start date for data TIME-OBS = / Start time for data DATE-END = / End date for data TIME-END = / End time for data TIMESYS = / Time will be UTC MJDREFI = / 2010 expressed in UTC/Integer MJDREFF = / 2010 expressed in UTC/Fractional TIMEZERI = / Clock correction integer TIMEZERF = / clock correction fraction TIMEDEL = / integration time TIMEUNIT / Unit TSTARTT = / start time TSTARTI = / integer observation start time TSTARTF = / fractional observation start time TSTOP = / stop time TSTOPI = / integer observation stop time TSTOPF = / fractional observation stop time CHECKSUM = / HDU checksum updated 2016-10-03T03:57:26 DATASUM = / data unit checksum updated 2016-10- 03T03:57:26 END

3.6.2 TCT Header FITS format XTENSION = 'BINTABLE' / Binary table extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional Binary Table NAXIS1 = 24 / Width of table in bytes NAXIS2 = / Number of rows in table PCOUNT = 0 / Size of special data area GCOUNT = 1 / one data group (required keyword) TFIELDS = 3 / Number of fields in each row TTYPE1 = 'SPS_TIME' / label for field 1 TFORM1 = / data format of field: 8-byte DOUBLE TUNIT1 = / physical unit of field TTYPE2 = / label for field 2 TFORM2 = / data format of field: 8-byte DOUBLE TUNIT2 = / physical unit of field TTYPE3 = / physical unit of field TFORM3 = / data format of field: 8-byte DOUBLE TUNIT3 = / physical unit of field EXTNAME = 'TCT ' / name of this binary table extension ORIGIN = / configuration control CREATOR = 'SXT-L1 ' / program that produced file HDUVERS = '1.4 ' / Version number of the format HDUCLASS = 'OGIP ' / format confirms to OGIP/GSFC standard HIERARCH = / Extension contains time correlation of HDUCLASS1 HIERARCH = / Extension contains time correlat HDUCLASS2 LONGSTRN = 'OGIP 1.0' / The OGIP long string convention may be used 37 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

CHECKSUM = / HDU checksum updated 2016-10- 03T03:57:26 DATASUM = / data unit checksum updated 2016-10- 03T03:57:26 END

3.7 MKF FILE AS1sxt_level2.mkf Where OBSID is observation ID, MM is the Mode, WW is the mode status bit.

3.7.1 Primary Header FITS format SIMPLE = T / file does conform to FITS standard BITPIX = 16 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may include extensions ORIGIN = 'ASTROSAT-SXT-L1' / Configuration control CREATOR = 'SXT-L1 ' / TELESCOP = 'ASTROSAT' / INSTRUME = 'SXT ' / DATE = / file creation date (YYYY-MM-DDThh:mm:ss UTC) DATE-OBS = / Start date for data TIME-OBS = / Start time for data DATE-END = / End date for data TIME-END = / End time for data TIMESYS = 'TT ' / Time will be UTC MJDREFI = / 2010.0(UTC) expressed in UTC (integer part) MJDREFF = / 2010.0(UTC) expressed in UTC (fractional part) TIMEZERI = / Clock correction integer TIMEZERF = / Clock correction fractional TIMEDEL = / Time resolution TIMEUNIT = 's ' / TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTOP Stop time TSTOPI = / integer observation stop time TSTOPF = / fractional observation stop time OBJECT = / Source information block RA_NOM = / Nominal Average pointing DEC_NOM = / Nominal Average pointing RA_REF Refernce pointing DEC_REF Refernce pointing EQUINOX = 2000.0 / J2000.0 RADECSYS = 'ICRF ' / Julian coordinate reference frame OBSERVER = / Observation information block OBS_ID = / Observation information block

38 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

CHECKSUM = / HDU checksum updated 2016-10- 03T03:58:32 DATASUM = / data unit checksum updated 2016-10- 03T03:58:32 END

3.7.2 MKF Header FITS format XTENSION = 'BINTABLE' / Binary table Extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional Binary Table NAXIS1 = 114 / width of table in bytes NAXIS2 = / number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / One data group (required keyword) TFIELDS = 36 / number of fields in each row

TTYPE1 = 'Time ' / label for field 1 TFORM1 = '1D ' / data format of field: 8-byte DOUBLE TUNIT1 = 'seconds ' / physical unit of field EXTNAME = 'MKF2 ’ / name of this binary table extension

TTYPE2 = ANG_OFFSET / label for field TFORM2 = 'D ' / format of field / TTYPE3 = BR_EARTH / label for field TFORM3 = 'D ' / format of field / TTYPE4 = ELV / label for field TFORM4 = 'E ' / format of field / TTYPE5 = TARGET_IN_FOV / label for field TFORM5 = ' I ' / format of field TNULL5 = / NULL value / TTYPE6 = 'MOON_ANGLE' / label for field TFORM6 = 'E ' / format of field / TTYPE7 = RAM_ANGLE / label for field TFORM7 = 'E ' / format of field / TTYPE8 = SAA_FLAG / label for field TFORM8 = 'I ' / format of field TNULL8 = 'deg ' / NULL value / TTYPE9 = TIME_SINCE_SAA / label for field TFORM9 = 'E ' / format of field / TTYPE10 = SUN_ANGLE / label for field TFORM10 = 'E ' / format of field

TTYPE11 = ROLL_DEC / label for field TFORM11 = 'D ' / format of field / TTYPE12 = ROLL_RA / label for field TFORM12 = 'D ' / format of field

39 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

/ TTYPE13 = ROLL_ROT / label for field TFORM13 = 'D ' / format of field / TTYPE14 = label for field / label for field TFORM14 = 'E ' / format of field = / TTYPE15 = label for field / label for field TFORM15 = 'E ' / format of field / TTYPE16 = Vod / label for field TFORM16 = 'E ' / format of field / TTYPE17 = Vrd / label for field TFORM17 = 'E ' / format of field = / TTYPE18 = Vgr / label for field TFORM18 = 'E ' / format of field / TTYPE19 = Vog / label for field TFORM19 = 'E ' / format of field / TTYPE20 = Vss_Vbk / label for field TFORM20 = 'E ' / format of field / TTYPE21 = LED_on_of / label for field TFORM21 = 'I ' / format of field TNULL21 NULL value / TTYPE22 = Amp_Gain_H_L / label for field TFORM22 = 'I ' / format of field TNULL22 NULL value / TTYPE23 = Cam_Door_Open / label for field TFORM23 = 'I ' / format of field TNULL23 NULL value / TTYPE24 = CPM_Rate / label for field TFORM24 = 'J ' / format of field = / TTYPE25 = Vid / label for field TFORM25 = 'E ' / format of field / END

3.8 LBT HK file AS1sxt_level2.lbt Where OBSID is observation ID, MM is the Mode, WW is the mode status bit. 40 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

3.8.1 Primary Header FITS format SIMPLE = T / HDU 0 BITPIX = 8 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may include extensions ORIGIN = 'ASTROSAT-SXT-L2' / Configuration control CREATOR = 'SXT-L2 ' / TELESCOP = 'ASTROSAT' / INSTRUME = 'SXT ' / CHECKSUM = / ASCII encoded HDU checksum DATASUM = / Data unit checksum written in ASCII DATE = / file creation date (YYYY-MM-DDThh:mm:ss UTC) DATE-OBS = / Start date for data TIME-OBS = / Start time for data DATE-END = / End date for data TIME-END = / End time for data TIMESYS = 'TT ' / Time will be TT (Terrestrial Time) MJDREFI = / 2010.0(UTC) expressed in TT (integer part) MJDREFF = / 2010.0(UTC) expressed in TT (fractional part) / MJ = JD - 2400000.5 TIMEZERI = / Clock correction integer TIMEZERF = / Clock correction fractional TIMEDEL = / Time resolution TIMEUNIT = 's ' / TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTOPI = / integer observation stop time TSTOPF = / fractional observation stop time OBJECT = / Source information block RA_PNT = / Nominal pointing DEC_PNT = / Nominal pointing EQUINOX = 2000.0 / J2000.0 RADECSYS = 'ICRF ' / Julian coordinate reference frame OBSERVER = / Observation information block OBS_ID = / END

3.8.2 LBT HK Header FITS format XTENSION = 'BINTABLE' / HDU 1 BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional Binary Table NAXIS1 = 180 / Number of bytes per row NAXIS2 = / Number of rows PCOUNT = 0 / No group parameters (required keyword) GCOUNT = 1 / One data group (required keyword) TFIELDS = 57 / Number of columns EXTNAME = 'SXT-LBTHK’ / SXT LBT HK DATA ORIGIN = 'SXT-L2 ' /

41 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

CREATOR = 'SXT-L2 ' / HDUVERS = '1.0.0 ' / HDUCLASS = 'OGIP ' / LONGSTRN = 'OGIP 1.0' / The OGIP long string convention may be used. CHECKSUM = / HDU checksum DATASUM = / Data checksum, ASCII encoded / TTYPE1 = 'Time ' / Time : Time stamp (sec since 1 Jan 2010) TUNIT1 = 's ' / TFORM1 = 'D ' / format of field / TTYPE2 = 'Vod ' / CCD Bias Drain Voltage TFORM2 = 'E ' / format of field / TTYPE3 = 'Vrd ' / CCD Reference Bais Voltage TFORM3 = 'E ' / format of field / TTYPE4 = 'Vgr ' / CCD guard Bias Voltage TFORM4 = 'E ' / format of field / TTYPE5 = 'Vid ' / CCD i/p diode Bias Voltage TFORM5 = 'E ' / format of field / TTYPE6 = 'Vog ' / CCD o/p gate Bias Voltage TFORM6 = 'E ' / format of field / TTYPE7 = 'Vss_Vbk ' / CCD substrate Bias Voltage TFORM7 = 'E ' / format of field / TTYPE8 = 'Reset_clock' / CCD Reset Clock level TFORM8 = 'E ' / format of field / TTYPE9 = 'I_S_Clock' / CCD I/S Clock level TFORM9 = 'E ' / format of field / TTYPE10 = 'Ofset ' / Amplifier Ofset Voltage TFORM10 = 'E ' / format of field / TTYPE11 = 'R_Clock ' / CCD R Clock level TFORM11 = 'E ' / format of field / TTYPE12 = 'IG_Clock' / CCD IG Clock level TFORM12 = 'E ' / format of field / TTYPE13 = '+15V ' / Analog Voltage +15V TFORM13 = 'E ' / format of field / TTYPE14 = '-15V ' / Analog Voltage -15V TFORM14 = 'E ' / format of field / TTYPE15 = '+5VA ' / Analog Voltage +5VA TFORM15 = 'E ' / format of field / TTYPE16 = '+5VD ' / Digital Voltage +5VD TFORM16 = 'E ' / format of field / 42 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TTYPE17 = '-5VA ' / Analog Voltage -5VA TFORM17 = 'E ' / format of field / TTYPE18 = 'Hop1_A ' / Hop1 Coil A Voltage TFORM18 = 'E ' / format of field / TTYPE19 = 'Hop2_A ' / Hop2 Coil A Voltage TFORM19 = 'E ' / format of field / TTYPE20 = 'Temp_EL-03' / Temperature of card EL-03 TFORM20 = 'E ' / format of field / TTYPE21 = 'Temp_Bottom' / Temperature of DC-DC tray TFORM21 = 'E ' / format of field / TTYPE22 = 'FPGA1_2.5V' / FPGA1 core Voltage (2.5V) TFORM22 = 'E ' / format of field / TTYPE23 = 'FPGA1_3.3V' / FPGA1 I/O Voltage (3.3V) TFORM23 = 'E ' / format of field / TTYPE24 = 'FPGA3_2.5V' / FPGA3 core Voltage (2.5V) TFORM24 = 'E ' / format of field / TTYPE25 = 'FPGA3_3.3V' / FPGA3 I/O Voltage (3.3V) TFORM25 = 'E ' / format of field / TTYPE26 = 'CCD_Temp_1' / CCD Temperature_1 TFORM26 = 'E ' / format of field / TTYPE27 = 'CCD_Temp_2' / CCD Temperature_2 TFORM27 = 'E ' / format of field / TTYPE28 = 'Camera_Temp' / Camera Temperature TFORM28 = 'E ' / format of field / TTYPE29 = 'Cold_Figure' / Cold Finger Temperature TFORM29 = 'E ' / format of field / TTYPE30 = 'Camera_Vacuum' / Camera Vacuum TFORM30 = 'E ' / format of field / TTYPE31 = 'Hop_Raw ' / Hop Raw Voltage TFORM31 = 'E ' / format of field / TTYPE32 = 'TEC+ ' / TEC Heating Mode Voltage TFORM32 = 'E ' / format of field / TTYPE33 = 'TEC- ' / TEC Cooling Mode Voltage TFORM33 = 'E ' / format of field / TTYPE34 = '+12V ' / +12V Supply Voltage TFORM34 = 'E ' / format of field / TTYPE35 = 'TEC_Raw ' / TEC Raw Voltage TFORM35 = 'E ' / format of field 43 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

/ TTYPE36 = 'Bellow_Pressure' / Bellow Pressure TFORM36 = 'E ' / format of field / TTYPE37 = 'Event_Threshold' / Event Threshold TFORM37 = 'E ' / format of field / TTYPE38 = 'Set_CCD_Temp' / Set CCD Temperature TFORM38 = 'E ' / format of field / TTYPE39 = 'CCD_Count_per_frame / CCD Counts ' TFORM39 = 'J ' / format of field / TTYPE40 = 'Command_Counter' / Command Counter TFORM40 = 'I ' / format of field / TTYPE41 = 'Telescope_Door' / Telescope Door TFORM41 = 'I ' / format of field / TTYPE42 = 'TEC_mode' / TEC mode status TFORM42 = 'I ' / format of field / TTYPE43 = 'Crystal_1/2' / Crystal 1/2 selection TFORM43 = 'I ' / format of field / TTYPE44 = 'LED_on/of' / LED on/of selection TFORM44 = 'I ' / format of field / TTYPE45 = 'CCD_Read_L/R' / CCD Read L/R selection TFORM45 = 'I ' / format of field / TTYPE46 = 'LBT_M/R ' / LBT main/Redundant TFORM46 = 'I ' / format of field / TTYPE47 = 'Amp_Gain_H/L' / Amp Gain H/L selection TFORM47 = 'I ' / format of field / TTYPE48 = 'CCD_T1/T2_active' / CCD T1/T2 active selection TFORM48 = 'I ' / format of field / TTYPE49 = 'Full/Window' / CCD Full/Window TFORM49 = 'I ' / format of field / TTYPE50 = 'CCD_mode6' / CCD mode6 on/of TFORM50 = 'I ' / format of field / TTYPE51 = 'CCD_mode5' / CCD mode5 on/of TFORM51 = 'I ' / format of field / TTYPE52 = 'CCD_mode4' / CCD mode4 on/of TFORM52 = 'I ' / format of field / TTYPE53 = 'CCD_mode3' / CCD mode3 on/of TFORM53 = 'I ' / format of field / 44 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

TTYPE54 = 'CCD_mode2' / CCD mode2 on/of TFORM54 = 'I ' / format of field / TTYPE55 = 'CCD_mode1' / CCD mode1 on/of TFORM55 = 'I ' / format of field / TTYPE56 = 'TEC_Control_Volt' / TEC Control Voltage TFORM56 = 'E ' / format of field / TTYPE57 = 'AD ' / Sync Value TFORM57 = 'I ' / format of field END

45 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

3.9 Attitude File AS1sxt_level2.att Where OBSID is observation ID, MM is the Mode, WW is the mode status bit.

3.9.1 Primary Header FITS format SIMPLE = T / file does conform to FITS standard BITPIX = 16 / Number of bits per data pixel NAXIS = 0 / Number of data axes EXTEND = T / FITS dataset may include extensions ORIGIN = 'ASTROSAT-SXT-L1' / Configuration Control CREATOR = SXT-L1 TELESCOP = ASTROSAT INSTRUME = SXT DATE file creation date (YYYY-MM-DDThh:mm:ss UTC) DATE-OBS = / Start date for data DATE-END = / End date for data TIME-OBS = / Start time for data TIME-END = / End time for data TIMESYS UTC Time will be UTC MJDREFI = / 2010.0(UTC) expressed in UTC (integer part) MJDREFF = / 2010.0(UTC) expressed in UTC (fractional part) TIMEZERI Clock correction integer TIMEZERF Clock correction fractional TIMEDEL Time resolution DELTAT Time resolution TIMEUNIT = 's ' / TSTART Start time TSTARTI = / integer portion of start time TSTARTF = / fractional observation start time TSTOP = / Stop time TSTOPI = / integer observation stop time TSTOPF = / fractional observation stop time OBJECT = / Source information block RA_PNT = / Nominal pointing DEC_PNT = / Nominal pointing EQUINOX = 2000.0 / J2000.0 RADECSYS = 'ICRF ' / Julian coordinate reference frame OBSERVER = / Observation information block OBS_ID = / Observation information block CHECKSUM = / HDU checksum updated 2016-10-03T03:57:54 DATASUM = / data unit checksum updated 2016-10- 03T03:57:54 END

46 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

3.9.2 ATTITUDE Header FITS format XTENSION = 'BINTABLE' / Binary table Extension BITPIX = 8 / 8-bit bytes NAXIS = 2 / 2-dimensional Binary Table NAXIS1 = / width of table in bytes NAXIS2 = / Number of rows in table PCOUNT = 0 / size of special data area GCOUNT = 1 / One data group (required keyword) TFIELDS = 6 / number of fields in each row

TTYPE1 = 'Time ' / label for field 1 TFORM1 = 'D ' / data format of field: 8-byte DOUBLE TUNIT1 = 's ' / physical unit of field

TTYPE2 = 'Q_SAT ' / label for field 2 TFORM2 = '4D ' / data format of field: 8byte DOUBLE

TTYPE3 = 'Roll_RA ' / label for field 3 TFORM3 = '1D ' / data format of field: 8-byte DOUBLE TUNIT3 = 'deg ' / physical unit of field / TTYPE4 = 'Roll_DEC ' / label for field 4 TFORM4 = '1D ' / data format of field: 8-byte DOUBLE TUNIT4 = 'deg ' / physical unit of field

TTYPE5 = 'ROLL_ROT ' / label for field 5 TFORM5 = '1D ' / data format of field: 8-byte DOUBLE TUNIT5 = 'deg ' / physical unit of field

TTYPE6 = 'ATD_STATUS' / label for field 6 TFORM6 = '8X ' / data format of field: BIT

EXTNAME = 'ATTITUDE’ / name of this binary table extension ORIGIN = 'ASTROSAT-SXT-L1 ' / CREATOR = 'SXT-L1 ' / HDUVERS = '1.0.0 ' / HDUCLASS = 'OGIP ' / HDUCLAS1 = 'ATTITUDE' / LONGSTRN = 'OGIP 1.0' / The OGIP long string convention may be used. CHECKSUM = / HDU checksum updated 2016-10-03T03:57:54 DATASUM = / data unit checksum updated 2016-10- 03T03:57:54 END

47 Astrosat/DP/SAC/SIPA/SPDCG/HRDPD/TR-5(c)/Sept.2017

4.References [1] Astrosat Data Pipeline Requirements Document Version-2.5, May 09 [2] Astrosat (SXT) Data Pipeline Processing Document, AST-SXT- SOFTWARE-004, Nov. 2011 [3] Interface Control Document: Level1 Outputs version 1.3 ASTROSAT- GS-ICD-LEVEL1/VER1.3. [4] Observation Identification and Data File naming convention for the ASTROSAT mission prepared by Dipankar Bhattacharya, 11 Nov 2010, Version 0.8 (draft).