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FIRAS_DIFFERENTIAL_SKY_SPECTRA_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    = '30/07/97'           / 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-DIFF'           /  Differential sky 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= '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 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=                  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  =                 4234 / 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 =                   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                                                                             

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