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SPECTRA extension

The grid of spectra appear in the last extension as a BINTABLE called SPECTRA. The first element in each row is a vector of interpolation parameter values for that spectrum, the second is the spectrum, and the 3rd-(NADDPARM+2)th columns are the contributions due to the additional parameters. The parameter value column is PARAMVAL, the interpolated parameter column is INTPSPEC, and the additional parameter columns are ADDSPXXX. The spectra are ordered with the last parameter changing fastest eg if we have two parameters each of which takes three values (1,2,3) then the spectra are ordered (1,1), (1,2), (1,3), (2,1), (2,2), (2,3), (3,1), (3,2), (3,3).

This extension should also include the standard OGIP keywords :


HDUCLASS 		 'OGIP'           

HDUCLAS1 'XSPEC TABLE MODEL'
HDUCLAS2 'MODEL SPECTRA'
HDUVERS '1.0.0'


next up previous
Next: The WFTBMD routine Up: The FITS file format Previous: ENERGIES extension
Keith Arnaud
2005-05-10