Calculation of higher-order corrections to muon energy loss cross sections

• Applicant: Dr. Alexander Sandrock
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields ; Astrophysics and Astronomy
• Term: from 2019 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 426052557

• Final Report Year: 2022

Final Report Abstract

Precise simulations of high-energy muons are important for many applications in astroparticle physics, for example for neutrino observatories or cosmic ray experiments. The aim of this project was to improve the accuracy of muon energy loss cross sections using theoretical and simulation methods. We performed calculations of diffractive and radiative corrections to bremsstrahlung and pair production by high energy muons. Compared to the main contribution to bremsstrahlung, diffractive corrections turned out to be of the order 10^−3 , in contrast to earlier calculations by Kelner and Fedotov 1999 predicting corrections of several percent. By careful examination of these earlier calculations, mistakes in the numerical results of the earlier authors were identified. Diffractive corrections to pair production turned out to be smaller by about 2 orders of magnitude and therefore insignificant to energy loss calculations. In contrast, radiative corrections to the pair production cross section turned out to be of the order of more than a percent. Since the neutrino energy spectra in astroparticle physics are indirectly reconstructed using these cross sections, the corrections are also relevant for the reconstruction of atmospheric and astrophysical neutrino fluxes.

Publications

• (2020). “Feasibility study to measure the muon bremsstrahlung cross section with the energy loss profile using neutrino telescopes”. In: Journal of Physics: Conference Series 1690, p. 012020
  J. Soedingrekso et al.
  
• (2020). “PROPOSAL: A library to propagate leptons and high energy photons”. In: Journal of Physics: Conference Series 1690, p. 012021
  J.-M. Alameddine et al.
  
• (2020). “Theoretical uncertainties of muon transport calculations for very large volume neutrino telescopes”. In: Journal of Physics: Conference Series 1690, p. 012005
  A. Sandrock, R. P. Kokoulin, and A. A. Petrukhin
  
• (2021). “Diffractive Scattering of Virtual Photons on Nuclei and Its Interference with the Muon-Induced Bremsstrahlung Process”. In: Physics of Atomic Nuclei 84, p. 69
  A. Sandrock, E. V. Bugaev, et al.
  
• (2021). “Uncertainties of the energy loss by inelastic interactions of muons with nuclei”. In: 37th International Cosmic Rays Conference (ICRC2021). Vol. 395. Proceedings of Science, p. 1221
  A. Sandrock, E. V. Bugaev, et al.