XMM-Newton Science Analysis System
eregionanalyse (especget-1.54) [xmmsas_20230412_1735-21.0.0]
The radius of a circular extraction region which gives the
maximum signal to noise
ratio calculated from the source counts, the encircled energy function
and the background. The PSF type used to calculate the
encircled energy function may be changed using the parameter psfmodel.
This is output in arcseconds and in
the units of the image (i.e. detector or sky pixels). In the output
parameter optradius it is stored in image units.
XMM-Newton SOC -- 2023-04-16