Fast simulations

Hi GEANT4 gurus,

I am using GEANT4 to simulate a medical linear accelerator and the goal of my project is to compute absorbed dose for radiotherapy patient treatment plans. The particles of interest are photons (<7 MeV), electrons (<7 MeV), and positrons. Currently, it’s taking a long time to calculate the dose for a single patient plan (about a week on a 2-core CPU). I have over 90 plans to run. I am interested in accelerating the computing time and asking for suggestions here. Is there a GPU acceleration of GEANT4? I am most likely going to invest in more cores and run my simulation in parallel. Are there alternative pathways to speed up simulations? Thank you so much for reading.

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One option to accellerate simulations is to make use of biasing: Event Biasing Techniques — Book For Application Developers 10.7 documentation


There is no general GPU acceleration within Geant4 at the moment. One possibility for medical applications might be the extensions/applications MPEXS and/or GGEMS, but you would need to contact the developers of these for details. A search on the usual publication databases for “Geant4 GPU” will also produce a large number of hits, so you may be able to find some useful info/contacts through that.

Also a :+1: on @weller’s suggestion to look at biasing methods.

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Thank you for this suggestion. I am currently using directional bremsstrahlung splitting in my simulation. I will consider additional biasing techniques as well.

Thanks for providing this information. This is super helpful. I will look into these extensions. Have a good day!