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arXiv · 2108.03481

Hadron Interactions for Arbitrary Energies and Species, with Applications to Cosmic rays

Torbjörn Sjöstrand·Marius Utheim
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Abstract

The Pythia event generator is used in several contexts to study hadron and lepton interactions, notably $pp$ and $p\bar{p}$ collisions. In this article we extend the hadronic modelling to encompass the collision of a wide range of hadrons $h$ with either a proton or a neutron, or with a simplified model of nuclear matter. To this end we model $hp$ total and partial cross sections as a function of energy, and introduce new parton distribution functions for a wide range of hadrons, as required for a proper modelling of multiparton interactions. The potential usefulness of the framework is illustrated by a simple study of the evolution of cosmic rays in the atmosphere, and by an even simpler one of shower evolution in a solid detector material. The new code will be made available for future applications.

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Torbjörn Sjöstrand, Marius Utheim. 2021-08-07. Hadron Interactions for Arbitrary Energies and Species, with Applications to Cosmic rays. https://doi.org/10.1140/epjc%2Fs10052-021-09953-5

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