Generate source particles

Particles, Track, Event, Run and Biasing
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Geant4 Version:10.7.0
Operating System:linux
Compiler/Version:9.4.0
CMake Version:3.16.3

Dear Geant4 experts,
Could you please advise on how to implement a probability distribution function into Geant4 for sampling to generate a particle source? For example, how would I integrate the Maxwell-Boltzmann probability distribution function?

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Dear @Tang_Mao

Thank you for your question. One option is to generate the energy probability distribution offline, and sample later using your custom primary generator, or GSP [1]. This example shows how to use the GPS to load a custom distribution [2]

I hope this helps.

Best,

Alvaro

[1] Geant4 General Particle Source — Book For Application Developers 11.3 documentation

[2] geant4/examples/extended/eventgenerator/exgps/macros/test38.mac at master · Geant4/geant4 · GitHub

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Thank you for yur reply.

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Could you please explain the underlying principle of how the Geant4 General Particle Source (GPS) performs sampling from a user-defined distribution?