XMM-Newton Science Analysis System


specgroup (specgroup-1.7.1) [xmmsas_20230412_1735-21.0.0]

Statistical grouping

One of the following statistical tests may be applied to the data to calculate spectral groups.

1. Minimum number of counts
2. Minimum signal-to-noise ratio
3. Minimum ratio above the background

Only one of these may be selected otherwise the error MoreThanOneStatMethod will be issued.

The chosen statistic will be applied to the spectrum starting from the lowest to the highest bin (normally lowest to highest energy) by default. This may be reversed by setting the option hightolow=yes.

The treatment of the last group is user selectable (see section refspecgroup:options:lastbin).