Maximilian Reininghaus

Thinning and artificial fluctuations in air shower simulation

Monte Carlo simulations of extensive air showers induced by ultra-high-energy cosmic rays require lots of computation time and disk space. In order to mitigate these issues, the technique of "thin sampling" (or simply "thinning") was invented. Instead of tracking every individual daughter particle created in an interaction only a single one of them is randomly selected and assigned a statistical weight while the remaining daughter particles are removed from the simulation. This introduces additional, artificial fluctuations to shower observables. In my talk, I will give an introduction to the thinning technique and present recent results on our efforts to minimize these fluctuations by choosing appropriate probability distributions for the daughter particle selection depending on their respective energies.