TGenPhaseSpace normalization

Dear Experts,

I am interested in knowing the normalization of TGenPhaseSpace in ROOT. In other words, if I were to simply integrate over phase space (i.e. assuming matrix element squared = 1), what would be the answer? I ask because factors of (2*pi) need to be absorbed accordingly in the amplitude.


Maybe @moneta or @couet can help with this legacy physics class…

@moneta should know better than me.

TGenPhaseSpace generates the particle momentum for every event taking correctly into account the phase space. It is assumed a matrix element squared=1 and it returns an event weight , where you can apply the matrix element. The correct normalisation is taken care when generating the event.
You can find more information the technique used in this old reference,



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