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tudo-astroparticlephysics / PROPOSAL

Monte Carlo Simulation propagating charged Leptons through Media as C++ Library
GNU Lesser General Public License v3.0
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Change kinematic limits of BremsElectronScreening #308

Closed Jean1995 closed 2 years ago

Jean1995 commented 2 years ago

For BremsElectronScreening, the kinematic limits have so far been taken from Petrukhin & Shestakov, where the upper limit has been calculated by setting the corresponding screening function to zero.

However, we don't need to use this for BremsElectronScreening. Instead, we can just use the physical limit 1 - m/E. We have checked that this is still consistent with the condition that the screening function should be non-negative (see this presentation for more information)

Comparing PROPOSAL with EGS4, using these improved limits also yields a better agreement in the cross section (also shown in the presentation linked above).

This PR also fixes that the tables with the correction factors are stored as kinetic energies, but have been evaluated with total energies so far.

sudojan commented 2 years ago

Do I understand it correctly, that there are default limits for interactions, e.g. for Bremsstrahlung they are 0 and $1- m/E$, which can be overridden if a parametrization defines its own limits, which always have to be inside the default limits?