Shadowing effects in the diffractive scattering of virtual photons on nuclei and its interference with the process of bremsstrahlung

Abstract

In cosmic ray physics and high-energy neutrino astronomy, muons are ubiquitous. Due to their slow energy loss and consequently large range at high energies, the correct simulation of their transport through matter is especially important for underground experiments. The dominant energy loss processes are ionization and at higher energies pair production, bremsstrahlung and inelastic interaction with nuclei. A muon energy loss process, which has hitherto been neglected in such simulations, is the diffractive scattering of virtual photons on nuclei. As the elastic channel of this process has the same final state as the bremsstrahlung process (mu + A rightarrow mu + A + gamma ), an interference term arises, whose sign depends on the charge of the lepton. It is found that the contribution of this process was overestimated in earlier works and is significantly affected by shadowing.