TSpectrum

[aregjan]

Hi, I am trying to use the TSpectrum class to search for peaks in a
histogram. The documentaion on TSpectrum::Search is a bit
confusing…

hin: pointer to the histogram of source spectrum
sigma: sigma of searched peaks, for details we refer to manual

The manual has no reference whatsoever to this method, and only 3-4 references to the class in general (unless I am looking at the wrong manual?)

Anyhow, the way I understood sigma aught to be the expected width of the
peaks (in bins, or in abs. coordinate?). However, when I use what I expect it to be (like, 20), I get

root [54] Int_t n=spec->Search(arm_cut_2_2,20,"",0.5)
Error in <TSpectrum::SearchHighRes>: Too large clipping window

Through trial and error I found that this works only at sigma=3…

Any input on this?