FITS Headers


Primary Header

SIMPLE  =                    T /                                                
BITPIX  =                   16 / Number of bits per data pixel                  
NAXIS   =                    0 / Number of data axes                            
EXTEND  =                    T / FITS data may contain extensions               
DATE    = '2005-01-10'         / Creation date (CCYY-MM-DD) of FITS header      
COMMENT FITS (Flexible Image Transport System) format is defined in 'Astronomy  
COMMENT and Astrophysics', volume 376, page 359; bibcode 2001A&A...376..359H    
TELESCOP= 'COBE    '           /                                                
INSTRUME= 'DMR     '           /                                                
OBJECT  = 'ALL-SKY '           /                                                
COMMENT   This file contains the COBE-DMR 4-year sky map for the 31 GHz         
COMMENT   channel B data. This map was produced by Tony Banday and Gary         
COMMENT   Hinshaw in 1998 as follows. The final 4-year time-ordered             
COMMENT   differential data archive was converted to a calibrated archive       
COMMENT   in FITS format (the DMR 'CIO' data).  The WMAP prototype map-making   
COMMENT   software was adapted to the DMR experiment and used to generate       
COMMENT   these maps using the HEALPix tessellation of the sky.  As a check,    
COMMENT   the same archive and code were used to generate maps in the           
COMMENT   original COBE quad-cube pixelization. For the 31B channel (only)      
COMMENT   the maps differ slightly from the officially released COBE-DMR maps   
COMMENT   because of a difference in how the radiometer's magnetic              
COMMENT   susceptibility correction was applied.  In the original pipeline,     
COMMENT   the correction involved three separate fit coefficients for three     
COMMENT   separate time periods of usable data.  For technical reasons, the     
COMMENT   CIO-based pipeline used one fit coefficient for the correction of     
COMMENT   all three time periods.  Since the 31B channel has the least          
COMMENT   weight of the 6 DMR channels, this difference should be of no         
COMMENT   significant consequence.                                              
CHAN_ID = '31B     '           /                                                
FREQ    = '31 GHz  '           /                                                
REFERENC= 'C.L.Bennett, et.al., ApJL, 1996, 464, L1' /                          
REFERENC= 'A. Kogut, et al., ApJ, 1996, 470, 653' /                             
REFERENC= 'E.L. Wright, et al., ApJL, 1996, 458, L53' /                         
REFERENC= 'K.M. Gorski, et al., astro-ph/0409513' /                             
STOKES  = 'INTENSITY'          /                                                
EQUINOX =              2000.00 /                                                
SKYCOORD= 'GALACTIC'           /                                                
PIXTYPE = 'HEALPIX '           /                                                
ORDERING= 'NESTED  '           /                                                
RESOLUTN=                    5 /                                                
NSIDE   =                   32 /                                                
NPIX    =                12288 /                                                
FIRSTPIX=                    0 /                                                
LASTPIX =                12287 /                                                
DATE-BEG= '22/12/1989'         /Data set start date                             
JSTART  = '1989356000000000'   /Start time YYYYDDDHHMMSSHHH                     
DATE-END= '21/12/1993'         /Data set start date                             
JSTOP   = '1993355235959000'   /Stop time YYYYDDDHHMMSSHHH                      
COMMENT   DATE-BEG and DATE-END give the date during which                      
COMMENT   the earliest and the latest data used in this product                 
COMMENT   were obtained.                                                        

Extension Header 2

XTENSION= 'BINTABLE'           /binary table extension                          
BITPIX  =                    8 /8-bit bytes                                     
NAXIS   =                    2 /2-dimensional binary table                      
NAXIS1  =                    8 /width of table in bytes                         
NAXIS2  =                12288 /number of rows in table                         
PCOUNT  =                    0 /size of special data area                       
GCOUNT  =                    1 /one data group (required keyword)               
TFIELDS =                    2 /number of fields in each row                    
TTYPE1  = 'TEMPERATURE '       /                                                
TFORM1  = 'E       '           /Real*4 (floating point)                         
TUNIT1  = 'mK,thermodynamic'   /physical unit of field                          
TTYPE2  = 'N_OBS   '           /                                                
TFORM2  = 'E       '           /Real*4 (floating point)                         
TUNIT2  = 'counts  '           /physical unit of field                          
PIXTYPE = 'HEALPIX '           /HEALPIX pixelisation                            
ORDERING= 'NESTED  '           /Pixel ordering scheme, either RING or NESTED    
OBJECT  = 'FULLSKY '           /                                                
COORDSYS= 'G       '           /Pixelization coordinate system                  
NSIDE   =                   32 /Healpix resolution parameter                    
NPIX    =                12288 /Total number of pixels                          
FIRSTPIX=                    0 /First pixel # (0 based)                         
LASTPIX =                12287 /Last pixel # (zero based)                       
INDXSCHM= 'IMPLICIT'           /indexing : IMPLICIT or EXPLICIT                 
GRAIN   =                    0 /GRAIN = 0: No index,                            
COMMENT         G = Galactic, E = ecliptic, C = celestial = equatorial          
COMMENT         GRAIN =1: 1 pixel index for each pixel,                         
COMMENT         GRAIN >1: 1 pixel index for Grain consecutive pixels            

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