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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.
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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?
Muon Monte Carlo A tool for muon propagation simulation
Simulation of muon propagation Starting with Ei Ending with Ef 1.0 P(E)dx Stochastic losses vcut=0.05 f(E)dx Continuous losses Ecut=500 MeV
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 100 TeV 10-4 10-3
Method of propagation 0.05 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 100 TeV 0.05 10-4 10-4 10-3 10-3 0.01
Muon cross sections Ionization losses + knock-on electrons Bremsstrahlung 10 TeV muon Photonuclear Electron pair production Decay
Bremsstrahlung muons electrons
Photonuclear interaction Photon-nucleon Photonuclear
Muon propagator (MMC) settings: ph-nu settings photoproduction DIS Q2 soft hard 1 GeV2 Abramowicz Levin Levy Maor Bezrukov-Bugaev Butkevich-Mikheyev BB 1981 2002 1991 1997 ZEUS 94 Nuclear effects BB + Hard 03 Bugaev Shlepin Kokoulin 99 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
Electron, tau, and monopole muon electron tau monopole
Neutrino propagation Earth density profile is implemented Neutrino cross sections Also: nm ntoscillations
Interpolation errors Comparison: parameterized vs. non-parameterized Interpolation precision: (epa-enp)/epa vcut=0.01 vcut=10-4 vcut=10-4 Elow=10 TeV Distribution of the final energy of the muons that crossed 300 m of Frejus rock starting with 100 TeV 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 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 MUM LOH LIP MMC
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 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
Atmospheric lepton fluxes muons muon neutrinos electron neutrinos
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 IceCube, 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