Why the fluorescence number produced by gamma in scintillator is not right?

I want to simulate the transport of the fluorescence produced by gamma in scintillator, the photon yield is set by: mpt->AddConstProperty(“SCINTILLATIONYIELD”,1000./MeV);
the gamma energy is 1.1732MeV and 1.3325MeV, 50% probability separately, the energy deposition spectrum is


but fluorescence number distribution is:

there is no peak at 1173 and 1332? why?
when the photon yield is set by: mpt->AddConstProperty(“SCINTILLATIONYIELD”,100./MeV);
the fluorescence number distribution is:

so it seems the fluorescence number produced in one event is not related with the argument “SCINTILLATIONYIELD”, why?

the fluorescence number produced in one event concern other arguments?
what are they?

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The scintillation yield is the average number of optical photons produced per amount of energy loss of the primary particle. So, there are not expected to be peaks at the energy of the primary gamma.

Also, we had a bug in which neutral particles didn’t produce scintillation photons. This is fixed in 10.7.2.

I had encounter the same question.

I want to know, do you have the solution?

Thank you!

The number of scintillation photons per event is not (cannot) be defined. You can defined the number of photons per unit energy loss of the primary in a step, with SCINTILLATIONYIELD and friends.

Note it’s the energy loss of the primary, not the energy of the primary.