Within IRAF (if you have the 'ftools' package loaded), you can produce a PHA distribution. The recipe below is not elegant, but will suffice. The MARX files have 4096 PHA channels defined for ACIS, thus the main problem is to rebin the data to a reasonable number of PHA channels. Our example uses the ACIS-S back illuminated chip, S3, called 7 in the MARX system. We are interested in the ACIS spectrum, and thus no grating is employed. We start with the qpoe file generated by marx2qpoe with chip coordinates.
Procedure to create an XSPEC PHA FITS file from a MARX Event qpoe file.
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