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XMM-Newton Science Analysis System

eregionanalyse (especget-1.54) [xmmsas_20230412_1735-21.0.0]

Optimum radius

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