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SmileiPIC / Smilei

Particle-in-cell code for plasma simulation
https://smileipic.github.io/Smilei
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No positrons created with Landau-Lifshitz #147

Closed Viveal closed 4 years ago

Viveal commented 5 years ago

I used the benchmark file tst1d_10_pair_electron_laser_collision.py and tried to change the radiation model to LL. For MC it created positrons but for Landau-Lifshitz and the other models it didn't work. Would you be so kind to point out what I must change to be able to also generate positrons with LL? Here is my input file: tst1d_10_pair_electron_laser_collision.txt

MickaelGrech commented 5 years ago

Dear @Viveal,

The Landau-Lifshitz (LL) model, as well as corrected LL (cLL) and Fokker-Planck models, are valid for small electron quantum parameter (\chi < 1) for which no pair are expected. When you specify LL as your radiation model, only a radiation friction force is applied to the electrons, and most importantly no macro-photons are generated. Therefore, it is perfectly normal you cannot see pair production in that case! If you want to study pair production, you have to use the Monte-Carlo description of high-energy photon production and their back-reaction.

xxirii commented 5 years ago

Dear @Viveal, if you are satisfied with our reply let us know so that we can close this issue. Thanks