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specgroup (specgroup-1.7.1) [xmmsas_20211130_0941-20.0.0]

Minimum signal-to-noise ratio

This sets spectral groups such that each group contains a minimum signal-to-noise ratio (S/N). The calculation of the ratio will take the area-normalised background into account if a background spectrum is provided. e.g.:


\begin{code}{\em
specgroup spectrumset=srcspec.ds minSN=6.0 backgndset=bgdspec.ds
}\end{code}

would make groups with a minimum S/N of 6 where S/N is given by:

  $\displaystyle S/N = ( source - background * areanorm ) /
sqrt( source + background * areanorm^2)
$ (1)



XMM-Newton SOC -- 2021-11-30