I hope this is the right forum for my question:

I am using a binned LikelihoodMethod to compute an (“observed”) upper limit on the Zprime (to ttbar) prduction cross section, as function of a physical parameter ( Zprime mass).

Using the sum of (Standard Model) background processes, I also compute an expected upper limit as function of the physical parameter.

I would like to compute +/-1 and +/-2 sigma bands around the expected limit, in order to provide an estimate of how compatible a certain observed upper limit with the expected value of the limit.

I am wondering if there is a recommended way to compute the +/-1 and +/-2 sigma bands ?

so the code is attached

Thank you very much,

Wael

MC_Sig_500GeV_Bck.root (5.17 KB)

BinnedLikelihood.C (4.67 KB)