[en] In this thesis corrections to the energy loss cross sections of high-energy muons are calculated. Over a large part of the energy range investigated by very large volume neutrino telescopes such as IceCube, pair production and bremsstrahlung dominate the energy loss. The theoretical uncertainties on the energy loss cross sections influence the experimental results as systematic uncertainties. These corrections are important for the energy reconstruction of high-energy muons which are observed in particle and astroparticle detectors. The leading-order cross sections of bremsstrahlung and pair production have been parametrized with less approximations than in previous works. In the case of bremsstrahlung the differences are most pronounced at low muon energies, where bremsstrahlung is a very subdominant process, while at higher energies the difference to previous works is negligible. For pair production, the new parametrizations lead to changes of up to a percent to the cross section differential in the lost energy, and the differences are present at all energies. For bremsstrahlung, the next-to-leading-order (NLO) corrections have been calculated for the average energy loss and the differential cross section. The average energy loss is increased by about 2% in the high-energy limit due to these corrections. The relative effect on the differential cross section is independent of the energy of the muon in the approximation used here. The correction increases the cross section for large relative energy losses. For the inelastic nuclear interaction, NLO corrections have also been calculated. The correction to the cross section is also most pronounced for large relative energy losses; the correction is not independent of the muon energy for this process. For bremsstrahlung and pair production, Coulomb corrections, i. e. corrections to all orders in the coupling Za to the electric field of the nucleus have been calculated and parametrized, taking into account the nuclear formfactor. The qualitative behavior has been predicted earlier by other authors using simplified models for the nuclear charge distribution; this is the first quantitative calculation of Coulomb corrections for realistic extended nuclei.

[en] The energy reconstruction of high-energetic muons in the IceCube neutrino observatory is based on the energy losses through electromagnetic interactions. The systematic uncertainties of IceCube are among others the result of uncertainties in the muon cross-sections for bremsstrahlung, pair production and photonuclear interaction. This presentation gives a brief overview about the status of currently used parametrizations and a new calculation for the bremsstrahlung cross section that also takes into account higher order corrections.

[en] Over a large part of the energy range investigated by very large volume neutrino telescopes such as IceCube, pair production and bremsstrahlung dominate the energy loss of muons. The theoretical uncertainties on the energy loss cross sections influence the experimental results as systematic uncertainties. This contribution presents calculations of higher-order corrections to decrease these uncertainties for pair production and bremsstrahlung.

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[en] High-energy muons can travel large thicknesses of matter. For underground neutrino and cosmic ray detectors the energy loss of muons has to be known accurately for simulations. The processes through which muons loose energy are ionization, direct pair production, bremsstrahlung and inelastic nuclear interaction. Next-to-leading order corrections to the bremsstrahlung energy loss are presented.

No abstract available

[en] IceCube is a cubic kilometer scaled neutrino telescope detecting the Cherenkov light of charged particles propagating through the detector. To improve the reconstruction of the measured events, the systematic uncertainties have to be reduced in the simulation chain. PROPOSAL is a part of the IceCube simulation chain propagating charged leptons. This talk deals with recent improvements in PROPOSAL which can be separated into two topics: On the one hand physical aspects were enhanced to increase the precision of the propagation and reduce the systematic uncertainties. On the other hand programming aspects were improved to increase the performance and simplify usage and maintenance.

[en] The IceCube Neutrino Observatory at the South Pole is a Cherenkov detector designed to measure astrophysical neutrinos of all flavors. High energy tau neutrinos interacting inside the detector produce two cascades separated by the tau lepton decay length. At energies above 100 TeV the spatial separation can be resolved within the waveform of one IceCube optical module and identified as a double pulse signature. This work aims to select events with a cascade-like topology that contain at least one double pulse signature. This talk gives an overview over the current status of this analysis and its prospects.

[en] 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 (μ + A → μ + A + γ), 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.

No abstract available