One can then define (via evselect
called with withzcolumn=Y
a `corrected' spectrum within region
(usually in sky coordinates)
and its associated error :
In terms of the usual `uncorrected' spectrum:
The corresponding source spectrum is also obtained by summing
over the region, and the model spectrum (to be compared to the data)
by multiplying with the central effective area
and applying the response matrix.
arfgen arfset=your_arf spectrumset=your_spectrum withbadpixcorr=N modelee=N \ withdetbounds=Y filterdss=N detmaptype=flat detxbins=1 detybins=1 \ withsourcepos=Y sourcecoords=tel sourcex=0 sourcey=0
Model fitting may be performed via XSPEC, entering as RATE, and as STAT_ERR, with and in the Ancillary Response File and Redistribution Matrix File, respectively.
Note that the weighting procedure is incompatible with using the Poisson model (C-statistic) in XSPEC (the formula must be used). This means that care must be taken to have enough counts per spectral bin.
XMM-Newton SOC -- 2021-11-30