Which physics processes for x-ray studies?


I want to simulate some x-ray scenarios, while the upper energy limit would be of 4 MeV but mainly much lower at around 0.5 MeV or so.
Is there any argument against using just all available processes?

Thank you!

Hi, I would use G4EmStandardPhysics_option4. Depending on your specific simulation set-up, you may want to make sure you have fluorescence and eventualluy Auger eletron emission activated.

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Thank you!
Could you also please shed some light on me? Why especially this option and not using the entire EM range?
And also, why not all available processes like optical and hadronic and so on?

The EM physics builders are mutually exclusive. Each individual “_optionX” builds a complete set of EM processes, but with different models and other configurations, optimized for different kinds of physics. For instance, with 10 GeV pions hitting a sampling calorimeter, we don’t need or care about K and L edges.

You asked about “physics processes for X-ray studies.” If you also want optical physics and hadronic phyics (i.e., stuff at the several GeV energy scale), you are certainly free and welcome to include those in your overall physics list.

You might find the Geant4 Physics List Guide useful to you.

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In addition to what said by @mkelsey, please look at this paper where some “optionX” physics lists are described: Report on G4-Med, a Geant4 benchmarking system for medical physics applications developed by the Geant4 Medical Simulation Benchmarking Group - PubMed

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