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specgroup (specgroup-1.7.1) [xmmsas_20211130_0941-20.0.0]

Treatment of the last bin and other ungrouped bins

In the case where the last few bins of the spectrum do not meet the required statistical criterion for a normal group it may be treated in several ways:

  1. Leave the bins ungrouped and set their quality to bad:


  2. Group them and set their quality good:


  3. Add these bins into the final group:


The default is to add these bins onto the adjacent group. A different option may be selected by e.g.

specgroup spectrumset=srcspec.ds mincounts=25 lastbin=''setbad''

In principle, a set of user-defined ranges could leave ungrouped bins in the middle of the spectrum. These will also be treated according to the lastbin parameter setting.

XMM-Newton SOC -- 2021-11-30