FITS Headers
FIRAS_DIFFERENTIAL_CAL_SPECTRA_RLSS.FITS
Primary Header
SIMPLE = T / file does conform to FITS standard
BITPIX = 32 / number of bits per data pixel
NAXIS = 0 / number of data axes
EXTEND = T / FITS dataset may contain extensions
COMMENT FITS (Flexible Image Transport System) format defined in Astronomy and
COMMENT Astrophysics Supplement Series v44/p363, v44/p371, v73/p359, v73/p365.
COMMENT Contact the NASA Science Office of Standards and Technology for the
COMMENT FITS Definition document #100 and other FITS information.
DATE = '29/07/97' / FITS file creation date (dd/mm/yy)
ORIGIN = 'CDAC ' / Cosmology Data Analysis Center
TELESCOP= 'COBE ' / COsmic Background Explorer satellite
INSTRUME= 'FIRAS ' / COBE instrument [DIRBE, DMR, FIRAS]
OBJECT = 'ALL-SKY ' / part of sky given [ALL-SKY, GAL-SLICE]
PRODUCT = 'CAL-DIFF' / Differential calibration spectra
EQUINOX = 2000.0 / equinox of coords in following tables
COMMENT
REFERENC= 'For additional information, please refer to the' /
REFERENC= 'COBE Far Infrared Absolute Spectrophotometer (FIRAS)' /
REFERENC= 'Explanatory Supplement, ed. J.C. Mather et al,' /
REFERENC= 'COBE Ref. Pub. No. 97-C (Greenbelt, MD: NASA/GSFC),' /
REFERENC= 'available in electronic form from the NSSDC.' /
COMMENT
COMMENT COBE specific keywords
DATE-BEG= '24/11/89' / date of initial data represented (dd/mm/yy)
DATE-END= '21/09/90' / date of final data represented (dd/mm/yy)
PIXRESOL= 6 / Quad tree pixel resolution [6, 9]
COMMENT
COMMENT FIRAS specific keywords
CHANSCAN= 'RLSS ' / Channel and mirror transport mechanism scan
COMMENT / mode identifier. The first two characters
COMMENT / indicate the channel, the first being the
COMMENT / instrument side: right (R) or left (L); and
COMMENT / the second being the frequency: high (H) or
COMMENT / low (L). The third and fourth characters
COMMENT / indicate the scan mode, the third being the
COMMENT / scan length: short (S) or long (L); and the
COMMENT / fourth being the scan speed: slow (S) or
COMMENT / fast (F). In addition, the scan mode may
COMMENT / take the following values for low frequency
COMMENT / data only (channel = RL or LL):
COMMENT / FS: decimated SF data;
COMMENT / FL: truncated LF data.
MODLLABL= 'PASS4 ' / FIRAS calibration model solution label
MISS_SEG= 'ENTIRE_MISSION' / FIRAS segment of mission represented
NU_ZERO = 68.020812 / Optical frequency of initial data point in GHz
DELTA_NU= 13.604162 / Optical frequency interval between data points
COMMENT / in GHz
NUM_FREQ= 43 / Number of frequency points with good data
FFT_LENG= 640 / Length of Fast Fourier Transform used
END
Extension Header 2
XTENSION= 'BINTABLE' / Extension type is Binary Table
BITPIX = 8 / Binary data
NAXIS = 2 / Data are in a table
NAXIS1 = 4234 / Number of 8 bit bytes in each row
NAXIS2 = 515 / Number of rows
PCOUNT = 0 / Number of bytes of data following table
GCOUNT = 1 / Group count (always 1 for bintable extensions)
TFIELDS = 35 / Number of fields (columns) in the table
COMMENT
TIMVERSN= 'OGIP/93-003' / OGIP memo number where the convention
COMMENT / is described
COMMENT The times reported in this file are atomic seconds elapsed
COMMENT since 00:00:00 UTC, 1 January 1981. Time information is
COMMENT recorded in a manner consistent with the convention specified
COMMENT in OGIP/93-003 with the understanding that time is counted
COMMENT in atomic seconds and the origin of time (MJDREF) is quoted
COMMENT in ephemeris MJD.
TIMESYS = '1981.00 ' / time system (same as IRAS)
MJDREFI = 44605 / Integer portion of ephemeris MJD
COMMENT / corresponding to 0h UTC 1 Jan 1981
MJDREFF = 0.00059240741 / Fractional portion of ephemeris MJD
COMMENT / corresponding to 0h UTC 1 Jan 1981
TIMEUNIT= 's ' / unit for TSTART, TSTOP, TIMEZERO = seconds
TSTART = 280713605.000 / observation start time in TIMESYS system
TSTOP = 306806405.990 / observation stop time in TIMESYS system
COMMENT
COMMENT
COMMENT FIRAS Spectrum
COMMENT Project Dataset Record Structure
COMMENT
COMMENT
COMMENT Instrument Attitude Information
COMMENT
COMMENT FIRAS pixel number (resolution 6)
TFORM1 = '1J ' /
TTYPE1 = 'PIXEL ' / entire fieldname = PIXEL
TUNIT1 = ' ' /
COMMENT Galactic longitude, in deg (0 -> 360)
TFORM2 = '1E ' /
TTYPE2 = 'GAL_LON ' / entire fieldname = GAL_LON
TUNIT2 = 'deg ' /
COMMENT Galactic latitude, in deg (-90 -> +90)
TFORM3 = '1E ' /
TTYPE3 = 'GAL_LAT ' / entire fieldname = GAL_LAT
TUNIT3 = 'deg ' /
COMMENT Ecliptic longitude, epoch 2000.0, in deg (0 -> 360)
TFORM4 = '1E ' /
TTYPE4 = 'ECL_LON ' / entire fieldname = ECL_LON
TUNIT4 = 'deg ' /
COMMENT Ecliptic latitude, epoch 2000.0, in deg (-90 -> +90)
TFORM5 = '1E ' /
TTYPE5 = 'ECL_LAT ' / entire fieldname = ECL_LAT
TUNIT5 = 'deg ' /
COMMENT Right ascension, in deg (0 -> 360)
TFORM6 = '1E ' /
TTYPE6 = 'RA ' / entire fieldname = RA
TUNIT6 = 'deg ' /
COMMENT Declination, in deg (-90 -> +90)
TFORM7 = '1E ' /
TTYPE7 = 'DEC ' / entire fieldname = DEC
TUNIT7 = 'deg ' /
COMMENT
COMMENT Spectrum and Sigmas
COMMENT
COMMENT Real part of spectrum, in MJy/sr
TFORM8 = '210E ' /
TDIM8 = '(210) ' /
TTYPE8 = 'REAL_SPE' / entire fieldname = REAL_SPECTRUM
TUNIT8 = 'MJy/sr ' /
COMMENT Imaginary part of spectrum, in MJy/sr
TFORM9 = '210E ' /
TDIM9 = '(210) ' /
TTYPE9 = 'IMAG_SPE' / entire fieldname = IMAG_SPECTRUM
TUNIT9 = 'MJy/sr ' /
COMMENT Sigmas of spectrum, in MJy/sr
TFORM10 = '210E ' /
TDIM10 = '(210) ' /
TTYPE10 = 'SIGMAS ' / entire fieldname = SIGMAS
TUNIT10 = 'MJy/sr ' /
COMMENT
COMMENT Number and Times of IFGs
COMMENT
COMMENT Number of IFGs in spectrum
TFORM11 = '1J ' /
TTYPE11 = 'NUM_IFGS' / entire fieldname = NUM_IFGS
TUNIT11 = ' ' /
COMMENT Glitch rate for spectrum, in glitches/s
TFORM12 = '1E ' /
TTYPE12 = 'GLITCH_R' / entire fieldname = GLITCH_RATE
TUNIT12 = 'gl/s ' /
COMMENT Glitch rate weighted number of IFGs in spectrum
TFORM13 = '1E ' /
TTYPE13 = 'ADJ_NUM_' / entire fieldname = ADJ_NUM_IFGS
TUNIT13 = ' ' /
COMMENT Average data collection time in seconds since
COMMENT 00:00.00 UTC, 1 January 1981
TFORM14 = '1D ' /
TTYPE14 = 'TIME ' / entire fieldname = TIME
TUNIT14 = 's ' /
COMMENT Observation times of IFGs in the spectrum;
COMMENT in hundredths of days since ejection of the
COMMENT FIRAS aperture cover at
COMMENT 11:18.00 UTC, 21 November 1989
TFORM15 = '100J ' /
TDIM15 = '(100) ' /
TTYPE15 = 'IFG_TIME' / entire fieldname = IFG_TIMES
TUNIT15 = 'd*100 ' /
COMMENT Flag indicating orphan IFGs, which occur
COMMENT when a spectrum is composed of only 1 or
COMMENT 2 IFGs. In all other cases, the spectrum
COMMENT is composed of three or more IFGs;
COMMENT applicable only to sky data.
COMMENT Flag = 1 indicates 1 or 2 IFGS in the spectrum;
COMMENT flag = 0 indicates 3 or more IFGs in the spectrum.
TFORM16 = '1B ' /
TTYPE16 = 'ORPHANS ' / entire fieldname = ORPHANS
TUNIT16 = ' ' /
COMMENT
COMMENT Template Information
COMMENT
COMMENT Number of templates subtracted from spectrum
TFORM17 = '1J ' /
TTYPE17 = 'NUM_TEMP' / entire fieldname = NUM_TEMPLATES
TUNIT17 = ' ' /
COMMENT Number of IFGS used in forming the templates
TFORM18 = '1J ' /
TTYPE18 = 'TPL_NUM_' / entire fieldname = TPL_NUM_IFGS
TUNIT18 = ' ' /
COMMENT Flag indicating use of IFGs from neighboring
COMMENT pixels in template formation (suitable
COMMENT IFGs from 8 neighboring pixels);
COMMENT applicable only to sky data.
COMMENT Flag = 1 indicates neighbor IFGs were used;
COMMENT flag = 0 indicates neighbor IFGs were not used.
TFORM19 = '1B ' /
TTYPE19 = 'NEIGHBOR' / entire fieldname = NEIGHBORS
TUNIT19 = ' ' /
COMMENT Number of IFGS from neighboring pixels used in
COMMENT forming the templates; only for sky data
TFORM20 = '1J ' /
TTYPE20 = 'NBR_NUM_' / entire fieldname = NBR_NUM_IFGS
TUNIT20 = ' ' /
COMMENT Observation times of IFGs used in template
COMMENT formation; in seconds since
COMMENT 00:00.00 UTC, 1 January 1981
TFORM21 = '100D ' /
TDIM21 = '(100) ' /
TTYPE21 = 'TPL_TIME' / entire fieldname = TPL_TIMES
TUNIT21 = 's ' /
COMMENT Pixel numbers of IFGs used in templates
TFORM22 = '100J ' /
TDIM22 = '(100) ' /
TTYPE22 = 'TPL_PIXE' / entire fieldname = TPL_PIXELS
TUNIT22 = ' ' /
COMMENT
COMMENT Bolometer Response Function
COMMENT
COMMENT Commanded bolometer bias, in V
TFORM23 = '1E ' /
TTYPE23 = 'BOLOM_BI' / entire fieldname = BOLOM_BIAS
TUNIT23 = 'V ' /
COMMENT Bolometer readout voltage, in V
TFORM24 = '1E ' /
TTYPE24 = 'BOLOM_VO' / entire fieldname = BOLOM_VOLTAGE
TUNIT24 = 'V ' /
COMMENT Bolometer DC response, in V/W
TFORM25 = '1E ' /
TTYPE25 = 'DC_RESPO' / entire fieldname = DC_RESPONSE
TUNIT25 = 'V/W ' /
COMMENT Bolometer time constant, in s
TFORM26 = '1E ' /
TTYPE26 = 'TIME_CON' / entire fieldname = TIME_CONSTANT
TUNIT26 = 's ' /
COMMENT Linear autophase correction, in rad
TFORM27 = '1E ' /
TTYPE27 = 'PHASE_CO' / entire fieldname = PHASE_CORR
TUNIT27 = 'rad ' /
COMMENT
COMMENT Instrument Temperatures
COMMENT
COMMENT External calibrator temperature, in K
TFORM28 = '1E ' /
TTYPE28 = 'XCAL_TEM' / entire fieldname = XCAL_TEMP
TUNIT28 = 'K ' /
COMMENT Internal calibrator temperature, in K
TFORM29 = '1E ' /
TTYPE29 = 'ICAL_TEM' / entire fieldname = ICAL_TEMP
TUNIT29 = 'K ' /
COMMENT Sky horn temperature, in K
TFORM30 = '1E ' /
TTYPE30 = 'SKYHORN_' / entire fieldname = SKYHORN_TEMP
TUNIT30 = 'K ' /
COMMENT Reference horn temperature, in K
TFORM31 = '1E ' /
TTYPE31 = 'REFHORN_' / entire fieldname = REFHORN_TEMP
TUNIT31 = 'K ' /
COMMENT Dihedral mirror temperature, in K
TFORM32 = '1E ' /
TTYPE32 = 'DIHEDRAL' / entire fieldname = DIHEDRAL_TEMP
TUNIT32 = 'K ' /
COMMENT Collimator mirror temperature, in K
TFORM33 = '1E ' /
TTYPE33 = 'MIRROR_T' / entire fieldname = MIRROR_TEMP
TUNIT33 = 'K ' /
COMMENT Bolometer operating temperature, in K
TFORM34 = '1E ' /
TTYPE34 = 'BOLOM_TE' / entire fieldname = BOLOM_TEMP
TUNIT34 = 'K ' /
COMMENT Bolometer bath temperature, in K
TFORM35 = '1E ' /
TTYPE35 = 'BATH_TEM' / entire fieldname = BATH_TEMP
TUNIT35 = 'K ' /
COMMENT
END