FITS Headers
FIRAS_COADDED_SKY_INTERFEROGRAMS_LLFS.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 = '28/07/97' / 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 = 'SKY-IFG ' / Coadded sky interferograms
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= 'LLFS ' / 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 variance
COMMENT / point in GHz
DELTA_NU= 13.604162 / Optical frequency interval between variance
COMMENT / points in GHz
NUM_FREQ= 43 / Number of frequency points in variance
COMMENT / with good data
PEAK_POS= 90 / Interferogram peak position
FFT_LENG= 160 / 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 = 6266 / Number of 8 bit bytes in each row
NAXIS2 = 5048 / Number of rows
PCOUNT = 0 / Number of bytes of data following table
GCOUNT = 1 / Group count (always 1 for bintable extensions)
TFIELDS = 32 / 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 Coadded Interferogram
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 Coadded Interferogram and Variances
COMMENT
COMMENT Coadded interferogram, in counts
TFORM8 = '512E ' /
TDIM8 = '(512) ' /
TTYPE8 = 'COADDED_' / entire fieldname = COADDED_IFG
TUNIT8 = ' ' /
COMMENT Variance of real part of coadd spectrum, in (MJy/sr)^2
TFORM9 = '210E ' /
TDIM9 = '(210) ' /
TTYPE9 = 'REAL_VAR' / entire fieldname = REAL_VARIANCE
TUNIT9 = '(MJy/sr)^2' /
COMMENT Variance of imaginary part of coadd spectrum, in (MJy/sr)^2
TFORM10 = '210E ' /
TDIM10 = '(210) ' /
TTYPE10 = 'IMAG_VAR' / entire fieldname = IMAG_VARIANCE
TUNIT10 = '(MJy/sr)^2' /
COMMENT Covariance between real and imaginary
COMMENT parts of coadd spectrum, in (MJy/sr)^2
TFORM11 = '210E ' /
TDIM11 = '(210) ' /
TTYPE11 = 'REAL_IMA' / entire fieldname = REAL_IMAG_VARIANCE
TUNIT11 = '(MJy/sr)^2' /
COMMENT
COMMENT Number and Times of IFGs
COMMENT
COMMENT Number of IFGs in coadd
TFORM12 = '1J ' /
TTYPE12 = 'NUM_IFGS' / entire fieldname = NUM_IFGS
TUNIT12 = ' ' /
COMMENT Glitch rate for coadded IFG, in glitches/s
TFORM13 = '1E ' /
TTYPE13 = 'GLITCH_R' / entire fieldname = GLITCH_RATE
TUNIT13 = 'gl/s ' /
COMMENT Glitch rate weighted number of IFGs in coadd
TFORM14 = '1E ' /
TTYPE14 = 'ADJ_NUM_' / entire fieldname = ADJ_NUM_IFGS
TUNIT14 = ' ' /
COMMENT Average data collection time in seconds since
COMMENT 00:00.00 UTC, 1 January 1981
TFORM15 = '1D ' /
TTYPE15 = 'TIME ' / entire fieldname = TIME
TUNIT15 = 's ' /
COMMENT Observation times of IFGs in the coadd;
COMMENT in hundredths of days since ejection of the
COMMENT FIRAS aperture cover at
COMMENT 11:18.00 UTC, 21 November 1989
TFORM16 = '100J ' /
TDIM16 = '(100) ' /
TTYPE16 = 'IFG_TIME' / entire fieldname = IFG_TIMES
TUNIT16 = 'd*100 ' /
COMMENT Flag indicating orphan IFGs, which occur
COMMENT when a coadd is composed of only 1 or
COMMENT 2 IFGs. In all other cases, the coadd
COMMENT is composed of three or more IFGs;
COMMENT applicable only to sky data.
COMMENT Flag = 1 indicates 1 or 2 IFGS in the coadd;
COMMENT flag = 0 indicates 3 or more IFGs in the coadd.
TFORM17 = '1B ' /
TTYPE17 = 'ORPHANS ' / entire fieldname = ORPHANS
TUNIT17 = ' ' /
COMMENT
COMMENT Template Information
COMMENT
COMMENT Number of templates subtracted from coadded IFG
TFORM18 = '1J ' /
TTYPE18 = 'NUM_TEMP' / entire fieldname = NUM_TEMPLATES
TUNIT18 = ' ' /
COMMENT Number of IFGS used in forming the templates
TFORM19 = '1J ' /
TTYPE19 = 'TPL_NUM_' / entire fieldname = TPL_NUM_IFGS
TUNIT19 = ' ' /
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.
TFORM20 = '1B ' /
TTYPE20 = 'NEIGHBOR' / entire fieldname = NEIGHBORS
TUNIT20 = ' ' /
COMMENT Number of IFGS from neighboring pixels used in
COMMENT forming the templates; only for sky data
TFORM21 = '1J ' /
TTYPE21 = 'NBR_NUM_' / entire fieldname = NBR_NUM_IFGS
TUNIT21 = ' ' /
COMMENT Observation times of IFGs used in template
COMMENT formation; in seconds since
COMMENT 00:00.00 UTC, 1 January 1981
TFORM22 = '100D ' /
TDIM22 = '(100) ' /
TTYPE22 = 'TPL_TIME' / entire fieldname = TPL_TIMES
TUNIT22 = 's ' /
COMMENT Pixel numbers of IFGs used in templates
TFORM23 = '100J ' /
TDIM23 = '(100) ' /
TTYPE23 = 'TPL_PIXE' / entire fieldname = TPL_PIXELS
TUNIT23 = ' ' /
COMMENT
COMMENT Bolometer Bias and Voltage
COMMENT
COMMENT Commanded bolometer bias, in V
TFORM24 = '1E ' /
TTYPE24 = 'BOLOM_BI' / entire fieldname = BOLOM_BIAS
TUNIT24 = 'V ' /
COMMENT Bolometer readout voltage, in V
TFORM25 = '1E ' /
TTYPE25 = 'BOLOM_VO' / entire fieldname = BOLOM_VOLTAGE
TUNIT25 = 'V ' /
COMMENT
COMMENT Instrument Temperatures
COMMENT
COMMENT External calibrator temperature, in K
TFORM26 = '1E ' /
TTYPE26 = 'XCAL_TEM' / entire fieldname = XCAL_TEMP
TUNIT26 = 'K ' /
COMMENT Internal calibrator temperature, in K
TFORM27 = '1E ' /
TTYPE27 = 'ICAL_TEM' / entire fieldname = ICAL_TEMP
TUNIT27 = 'K ' /
COMMENT Sky horn temperature, in K
TFORM28 = '1E ' /
TTYPE28 = 'SKYHORN_' / entire fieldname = SKYHORN_TEMP
TUNIT28 = 'K ' /
COMMENT Reference horn temperature, in K
TFORM29 = '1E ' /
TTYPE29 = 'REFHORN_' / entire fieldname = REFHORN_TEMP
TUNIT29 = 'K ' /
COMMENT Dihedral mirror temperature, in K
TFORM30 = '1E ' /
TTYPE30 = 'DIHEDRAL' / entire fieldname = DIHEDRAL_TEMP
TUNIT30 = 'K ' /
COMMENT Collimator mirror temperature, in K
TFORM31 = '1E ' /
TTYPE31 = 'MIRROR_T' / entire fieldname = MIRROR_TEMP
TUNIT31 = 'K ' /
COMMENT Bolometer bath temperature, in K
TFORM32 = '1E ' /
TTYPE32 = 'BATH_TEM' / entire fieldname = BATH_TEMP
TUNIT32 = 'K ' /
COMMENT
END