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alcap-org / g4sim

Simulation toolkit based on Geant4 and ROOT
http://wuchen1106.github.io/g4sim/
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Have stopped muons emit more protons for the tolerances study #39

Open AndrewEdmonds11 opened 9 years ago

AndrewEdmonds11 commented 9 years ago

One of the suggestions in today's meeting that might require a change in the code is to have a setting so that we can assign how frequently stopped muons emit a proton.

I'll look into this and implement it soon.

thnam commented 9 years ago

I think some code similar to this is enough: https://github.com/alcap-org/g4sim/blob/master/src/MyDecayPhysics.cc#L105-L118

AndrewEdmonds11 commented 9 years ago

So I've had a look into this and I don't think that would be enough since the muon capture process is a bit more complicated than a simple phase space decay.

Currently, the muon capture process happens in Geant4 (G4MuonMinusCaptureAtRest::AtRestDoIt() and DoMuCapture()) which does the initial mu- + p --> nu + n process with the nucleons and then passes the resulting excited nucleus to G4ExcitationHandler for all the proton emission stuff.

We might be able to specify that we do capture 100% of the time rather than 60% by somehow setting lambdac and lambdad in G4MuonMinusCaptureAtRest but that would only be a small improvement.

At the moment, it's quicker for me to just re-run to get the necessary stats so I propose to put this on the back-burner for now.