XMM-Newton Science Analysis System


arfgen (arfgen-1.104) [xmmsas_20230412_1735-21.0.0]

Usage and Examples

Further information about the scientific use and accuracy of this task may be found in the document, XMM-SOC-PS-TN-0043, (available from http://xmm.vilspa.esa.es/external/xmm_sw_cal/calib/
documentation.shtml#EPIC/)
In order to execute arfgen correctly, the user should provide the following:

1. The appropriate values for the environment variables SAS_CCF and optionally SAS_ODF.

2. An input spectrum generated by xmmselect or evselect with the parameter writedss $=$ true,

3. a source position (optional). The user can use either the target position available from the input spectrum dataset by setting withsourcepos to false, or specify a different one by setting withsourcepos$=$true, and entering the coordinates and coordinate system through the parameters sourcex,sourcey and sourcecoords. (section 5.4)

4. If the detector map (a grid of positions used to calculate and flux weight the ARF: section 5.3) is either psf or flat, the map bounds and pixel size may be specified. For these types of map, the map bounds and pixel size by default will be automatically set to cover the regions over which the spectrum is accumulated, although the user has the option to set them explicitly if desired via the withdetbounds , withdetbins and associated parameters. Note that if a psf detector map is used, the energy at which the PSF model is taken may be specified. The user can supply an external detector map instead (section 5.3.2), but the bounds must cover the regions.

The user must then decide which models or corrections to apply (section 5.1), whether to use the energy grid from the CAL (withrmfset$=$false), or from an input RMF (withrmfset$=$true) [section 5.6] Finally, the user can, optionally, choose the name of the output ARF dataset through the arfset parameter.

The following sub-sections show examples of usage.