FITS

The FITS extension is an array of 80 character strings stored in a format identical to a standard FITS header. This contains general information about the observation but no array information. Listings of full SCUBA FITS headers can be found in Appendix . SURF only requires a subset of the full SCUBA headers. For a jiggle map these are listed in table .

Table: FITS keywords required by SURF for Jiggle mapping

OBJECT	Name of object
RUN	Run number of observation
MODE	Type of observation (MAP, PHOTOM, SKYDIP etc)
SAM_MODE	Sampling method (JIGGLE or RASTER)
SAM_CRDS	Coordinate frame of jiggle or scan
SAM_PA	Scan PA (not required for jiggle)
LAT	Latitude of object (eg Declination)
LONG	Longitude of object (eg Right Ascension)
CENT_CRD	Coordinate frame of LONG/LAT (RB,RJ,GA etc)
UTDATE	Date of observation in YYYY:MM:DD format
UTSTART	UT time of start of observation (HH:MM:SS)
STSTART	Local sidereal time of start of observation (HH:MM:SS)
STEND	LST of end of observation
EXP_TIME	Exposure time (seconds) of each individual sample
MAP_X	Tangent plane X offset from tracking centre
MAP_Y	Tangent plane Y offset from tracking centre
N_BOLS	Number of bolometers selected (should match data array)
STATE	State at end of observation (ABORT indicates early abort)
VERSION	Version of real-time software (see SURFLIB_PROCESS_BOLS)
JIGL_CNT	Number of offsets in jiggle pattern
J_PER_S	Number of jiggles per switch
J_REPEAT	No. of jiggle pattern repeats in switch
CNTR_DU3	Nasmyth dU3 coord of instrument centre
CNTR_DU4	Nasmyth dU4 coord of instrument centre
LAT-OBS	Latitude of observatory (degrees)
LONG-OBS	East longitude of observatory (degrees)
TELESCOP	Telescope name
INSTRUME	Instrument name
CHOP_THR	Chopper throw (arcsec)
CHOP_PA	Chopper PA 0=in lat, 90=in long
CHOP_FRQ	Chopper frequency (Hz)
CHOP_CRD	Coordinate frame of chop
CHOP_FUN	Chopper waveform (SQUARE, TRIPOS)
N_SUBS	Number of sub-instruments
SUB_1	Name of sub-instrument 1 (or 'not used')
SUB_2	Name of sub-instrument 2 (or 'not used')
SUB_3	Name of sub-instrument 3 (or 'not used')
SUB_4	Name of sub-instrument 4 (or 'not used')
SUB_5	Name of sub-instrument 5 (or 'not used')
FILT_1	Filter name for sub-instrument 1 (or 'not used')
FILT_2	Filter name for sub-instrument 2 (or 'not used')
FILT_3	Filter name for sub-instrument 3 (or 'not used')
FILT_4	Filter name for sub-instrument 4 (or 'not used')
FILT_5	Filter name for sub-instrument 5 (or 'not used')
WAVE_1	Wavelength of sub-instrument 1 (microns)
WAVE_2	Wavelength of sub-instrument 2 (microns)
WAVE_3	Wavelength of sub-instrument 3 (microns)
WAVE_4	Wavelength of sub-instrument 4 (microns)
WAVE_5	Wavelength of sub-instrument 5 (microns)