Transcript Muon Monte Carlo: a versatile tool for lepton propagation

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 Ei
Ending with Ef
1.0
P(E)dx
Stochastic losses
vcut=0.05
Ecut=500 MeV
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
TeV
-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
0.05
crossed 300 m of Frejus
rock starting with 10010
TeV
-4
10-4
-3 -3
1010
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
soft
1 GeV2
GVDM
CKMT
Bezrukov-Bugaev
BB 1981
Butkevich-Mikheyev
2002
ZEUS 94
Kokoulin 99
BB + Hard 03
Bugaev Shlepin
DIS
hard
Q2
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 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
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 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
muons
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 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
Applet demonstration