fbbft2pha -- Converts BATSE BFITS file to spectral PHA file
fbbft2pha bftfile phafile
This utility converts a BATSE BFITS file into a PHA ("Pulse Height Analyzer") spectral file that is compatible with the XSPEC spectral analysis package.
The output PHA files conform to the so-called OGIP Type II multispectral PHA file format. For a description of this format, see Arnaud et al., "The OGIP Spectral File Format," in Legacy, No. 2, pp. 65-76, November 1992.
This is an outline of the output BATSE PHA FITS file format:
Primary Array: Null data array
Extension # 1: BINTABLE 'SPECTRUM'
Col TTYPE TFORM TUNIT
^^^ ^^^^^^^^ ^^^^^ ^^^^^^^^
1 SPEC_NUM 1I none
2 CHANNEL nI chan
3 TSTART 1E s
4 TSTOP 1E s
5 RATE nE count /s
6 STAT_ERR nE count /s
where n is number of spectral channels
Conventionally, PHA files are intended for use with corresponding Redistribution Matrix Files (RMF) generated from the associated BATSE Detector Response Matrices (DRM) by the FTOOL fbdrm2rmf. The corresponding RMF is assumed to have the same name as the PHA file, but with a matching-case extension, .rmf or .RMF. The expected name of the RMF file appears in the PHA keyword RESPFILE.
For data types that are summed over multiple detectors, such as MER, the DETNAM keyword in the output PHA file shows all the used detector numbers concatenated together in the sub-instrument identifier label.
1. Convert BATSE MER BFITS file to PHA format suitable for XSPEC:
% fbbft2pha mer_bfits_143.fits mer_143.pha
fbdrm2rmf