Physics list

Todo

  • summary and peculiarities

  • optional components and options (hadronic, leptonic, optical)

  • production cuts and step limits

  • custom WLS optical process

  • custom Grabmayr gammacascades

  • simulating radioactive decay chains

optional components

Todo

  • optional components and options (hadronic, leptonic, optical)

hadronic physics options

Todo

  • hadronic physics options

Geant4 changed the default time threshold for radioactive decays in the 11.2 minor update to 1 year. remage automatically reverts this change and sets the threshold to the old default of Geant4 before 11.2, being 1.0e+27 ns. This threshold can be adjusted using the built-in command /process/had/rdm/thresholdForVeryLongDecayTime after /run/initialize.

Internal Bremsstrahlung

Todo

  • Internal Bremsstrahlung options

Internal Bremsstrahlung is a radiative correction to beta decay where a photon is emitted along with the beta particle and neutrino. Unlike external bremsstrahlung (which occurs when the beta particle interacts with matter after emission), internal bremsstrahlung is emitted directly from the nucleus during the decay process itself.

The IB photon energy spectrum is continuous, extending from zero up to the Q-value of the decay. For Ar-39 (Q = 565 keV), the IB photons are typically soft (low energy), with most photons below 0.5 MeV. The spectrum is calculated based on Hayen et al., Rev. Mod. Phys. 90, 015008 (2018). https://journals.aps.org/rmp/abstract/10.1103/RevModPhys.90.015008 The calculation is described in detail in Section V Radiative Correction.

The Inner Bremsstrahlung process is disabled by default in ReMage. To activate Inner Bremsstrahlung process, please use the command /RMG/Processes/EnableInnerBremsstrahlung before /run/initialize.