Muon Monte Carlo a versatile tool for lepton

Muon Monte Carlo: a versatile tool for lepton propagation through matter Dmitry Chirkin, UW, Madison, USA September 20, 2009, Ice. Cube collaboration meeting

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

MMC web page http: //icecube. wisc. edu/~dima/work/MUONPR/

Documentation: javadoc

Documentation: arxiv papers

Command-line options

Simulation of muon propagation Starting with Ei Ending with Ef 1. 0 P(E)dx Stochastic losses vcut=0. 05 Ecut=500 Me. V f(E)dx Continuous losses

Method of propagation 0. 05 10 -4 0. 05 0. 01 Distribution of the final energy of the muons that crossed 300 m of Frejus rock starting with 10010 Te. V -4 10 -3

Method of propagation 0. 05 10 -4 0. 05 0. 01 Distribution of the final energy of the muons that 0. 05 crossed 300 m of Frejus rock starting with 10010 Te. V -4 10 -4 -3 -3 1010 0. 01

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

Bremsstrahlung muons electrons

Photonuclear interaction Photon-nucleon Photonuclear

Muon propagator (MMC) settings: ph-nu settings photoproduction soft 1 Ge. V 2 GVDM CKMT Bezrukov-Bugaev BB 1981 ZEUS 94 Kokoulin 99 Butkevich-Mikheyev 2002 BB + Hard 03 Bugaev Shlepin DIS hard Q 2 ALLM Abramowicz Levin Levy Maor 1991 1997 Nuclear effects Dutta Smirnov

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 muon electron tau monopole

Neutrino propagation Earth density profile is implemented Neutrino cross sections Also: nm nt oscillations

Interpolation errors Comparison: parameterized vs. non-parameterized Interpolation precision: (epa-enp)/epa -4 vcut=10 =0. 01 Elow=10 Te. V Distribution of the final energy of the muons that crossed 300 m of Frejus rock starting with 100 Te. V Interpolation order: g=2, … 6

Algorithm errors: average propagation Deviation from average energy loss (with vcut=1) Propagating 4 106 muons through 100 m of Frejus rock

Algorithm errors: survival probability 106 muons with energy 9 Te. V 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 MUM LOH LIP

Number and energy of secondaries

Implementation for muon/neutrino detector 3 propagation regions: • before the detector: propagation with fixed vcut • inside the detector: propagation with fixed vcut or Ecut • after the detector: fast propagation with vcut=1. 0

Parameterization of atmospheric lepton fluxes with. CORSIKA 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 muon neutrinos electron neutrinos

Integrated fluxes

Quality of the fits fit quality stability 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 Ice. Cube, also in data analysis of Frejus • mmc is available at http: //icecube. berkeley. edu/~dima/work/MUONPR • 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