Muon Monte Carlo: a versatile tool for lepton propagation through matter Dmitry Chirkin, LBNL, Berkeley, USA October 31, 2006, Dortmund University

Introduction Muon propagation: why do we need it? Muon/neutrino detectors?

Particles observed by neutrino detectors

Muon Monte Carlo A tool for muon propagation simulation

Structure of the program

Simulation of muon propagation Starting with E i Ending with E f f(E)dx P(E)dx Continuous losses Stochastic losses 1.0 v cut =0.05 E cut =500 MeV

Method of propagation Distribution of the final energy of the muons that crossed 300 m of Frejus rock starting with 100 TeV

Method of propagation Distribution of the final energy of the muons that crossed 300 m of Frejus rock starting with 100 TeV

Muon cross sections Ionization losses + knock-on electrons Bremsstrahlung Photonuclear Electron pair production Decay 10 TeV muon

Bremsstrahlung muons electrons

Photonuclear interaction Photon-nucleonPhotonuclear

Q2Q2 1 GeV 2 softhard photoproductionDIS GVDMCKMTALLM Bezrukov-BugaevButkevich-Mikheyev Abramowicz Levin Levy Maor BB 1981 BB + Hard 03 Bugaev Shlepin ZEUS 94 Kokoulin 99 Nuclear effects DuttaSmirnov Muon propagator (MMC) settings: ph-nu settings

Mass effects Delta-correction to ionization (included into the ionization cross section) LPM suppression of the bremsstrahlung and direct electron pair production Dialectric suppression of the bremsstrahlung cross section

Moliere scattering

Electron, tau, and monopole muonelectron taumonopole

Neutrino propagation Neutrino cross sections Also:       oscillations Earth density profile is implemented

Interpolation errors Distribution of the final energy of the muons that crossed 300 m of Frejus rock starting with 100 TeV Comparison: parameterized vs. non-parameterized Interpolation precision: (e pa -e np )/e pa Interpolation order: g=2,…6 v cut =0.01v cut =10 -4 E low =10 TeV

Algorithm errors: average propagation Deviation from average energy loss (with v cut =1) Propagating muons through 100 m of Frejus rock

Algorithm errors: survival probability 10 6 muons with energy 9 TeV propagated through 10 km of water

Comparison with other codes: MUM (MUons + Medium) MUM code by E. Bugaev, I. Sokalski, S. Klimushin

Spectra of the secondaries MMC MUMLOH LIP

Number and energy of secondaries

Implementation for muon/neutrino detector 3 propagation regions: before the detector: propagation with fixed v cut inside the detector: propagation with fixed v cut or E cut after the detector: fast propagation with v cut =1.0

Parameterization of atmospheric lepton fluxes withCORSIKA Primaries with Z=1,…,26:Poli-gonato composition model Run CORSIKA Parameterize simultated fluxes with With corrections for zenith angle, muon energy loss and decay

Parameterization of the atmosphere

Muon energy losses

Atmospheric lepton fluxes muonsmuon neutrinoselectron neutrinos

Integrated fluxes

Quality of the fits fit qualitystability of the result

Things to remember mmc was written in 2000 and has been updated a few times with new cross sections and features mmc has been used by AMANDA and now IceCube, also in data analysis of Frejus mmc is available at mmc stands for Muon Monte Carlo and propagates muons perhaps more appropriate name is ALMC: All Lepton Monte Carlo, since it propagates muons, taus, electrons, all neutrinos mmc can also stand for monopole monte carlo

Applet demonstration