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Pixel list

In this example the image is given as a list of the energy and pixel coordinates of a set of detected photons. A 2-D image array could be generated from this list by making a 2-D histogram of the number of photons that were recorded in each pixel. The TLMINn and TLMAXn keywords shown below are not required, but are useful for recording the legal range of the values in each column and are used when constructing histograms of the values.

XTENSION= 'BINTABLE'           / binary table extension
BITPIX  =                    8 / 8-bit bytes
NAXIS   =                    2 / 2-dimensional binary table
NAXIS1  =                    8 / width of table in bytes
NAXIS2  =                10000 / number of rows in table
PCOUNT  =                    0 / size of special data area
GCOUNT  =                    1 / one data group (required keyword)

TFIELDS =                    3 / number of fields in each row
TTYPE1  = 'ENERGY  '           / energy of the photon 
TFORM1  = '1E      '           / data format of the field: R*8
TTYPE2  = 'X       '           / X pixel coordinate of the photon
TFORM2  = '1I      '           / data format of the field: ASCII Character
TTYPE3  = 'Y       '           / Y pixel coordinate of the photon
TFORM3  = '1I      '           / data format of the field: ASCII Character

TCTYP2  = 'RA---TAN'           / TAN projection used
TCRPX2  =                  150 / reference pixel
TCRVL2  =                45.83 / reference pixel
TCDLT2  =           -.00277777 / increment per pixel
TCUNI2  = 'deg     '           / physical units of axis 1
TLMIN2  =                    1 / lower limit of axis 1
TLMAX2  =                  300 / upper limit of axis 1

TCTYP3  = 'DEC--TAN'           / TAN projection used
TCRPX3  =                  100 / reference pixel
TCRVL3  =                63.57 / reference pixel
TCDLT3  =            .00277777 / increment per pixel
TCUNI3  = 'deg     '           / physical units of axis 2
TCROT3  =                 30.0 / image rotation (degrees)
TLMIN3  =                    1 / lower limit of axis 2
TLMAX3  =                  200 / upper limit of axis 2

TPC0202 =           .866025403 / Coord. Descrp. Matrix:  cos(TCROT2)
TPC0303 =                  -.5 / Coord. Descrp. Matrix: -sin(TCROT2)
TPC0203 =                   .5 / Coord. Descrp. Matrix:  sin(TCROT2)
TPC0302 =           .866025403 / Coord. Descrp. Matrix:  cos(TCROT2)

EQUINOX =               2000.0 / coordinate epoch
MJD-OBS =        44258.7845612 / MJD of the observation
END