FITS Headers
FIRAS_COADDED_CAL_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 = '24/07/97' / 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-IFG ' / Coadded calibration 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 = 69 / 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
