title: On the theory and simulation of multiple Coulomb scattering of heavy-charged particles.
abstract: The Moliere theory of multiple Coulomb scattering is modified to take into account the difference between processes of scattering off atomic nuclei and electrons. A simple analytical expression for angular distribution of charged particles passing through a thick absorber is found. It does not assume any special form for a differential scattering cross section and has a wider range of applicability than a gaussian approximation. A well-known method to simulate multiple Coulomb scatterings is based on treating 'soft' and 'hard' collisions differently. An angular deflection in a large number of 'soft' collisions is sampled using the proposed distribution function, a small number of 'hard' collision are simulated directly. A boundary between 'hard' and 'soft' collisions is defined, providing a precise sampling of a scattering angle (1% level) and a small number of 'hard' collisions. A corresponding simulating module takes into account projectile and nucleus charged distributions and exact kinematics of a projectile-electron interaction.
authors.affiliation: Accelerator Division, Fermi National Accelerator Laboratory, MS 220, Batavia, IL 60510-0500, USA. strigano@fnal.gov
authors.forename: S I
authors.initials: SI
authors.lastname: Striganov
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D020450:Heavy Ions; D008962:Models, Theoretical; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011874:Radiometry / Q000379:methods*; D012542:Scattering, Radiation; D055672:Static Electricity