[Gate-users] problem in optical photon simulation

[Amir Beheshti]

Dear GATE users,

I am simulating optical photons in a 4mmX4mmX20mm LSO crystal in GATE 9.0. 
I have a problem in outputs. I think the amount of scintillation photons is not correct. My source activity is 50 kBq of 511keV gamma and entries in LSO crystal is about 27000 photon. number of optical photon in the crystal is not logical. Would you
please tell me how do I obtain accurate number of optical photon produced in crystal?

Thanks a lot