# Presentation: 636109

## 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*

*0.05*

*10**-4*

*0.05*

*0.01*

*10**-3*

*10**-4*

## Method of propagation

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

*0.05*

*10**-4*

*0.05*

*0.01*

*10**-3*

*10**-4*

*0.05*

*0.05*

*0.01*

*10**-3*

*10**-4*

## Muon cross sections

*Ionization losses + knock-on electrons*

*Bremsstrahlung*

*Photonuclear*

*Electron pair production*

*Decay*

*10 TeV muon*

## Bremsstrahlung

*muons*

*electrons*

## Photonuclear interaction

*Photon-nucleon*

*Photonuclear*

## Q2

- Q2

- 1 GeV2

- soft

- hard

- photoproduction

- DIS

| GVDM | CKMT | ALLM |
| --- | --- | --- |

- Bezrukov-Bugaev

- Butkevich-Mikheyev

- Abramowicz Levin Levy Maor

- 1991

- 1997

- 2002

- BB 1981

- BB + Hard 03
- Bugaev Shlepin

- ZEUS 94

- Kokoulin 99

- Nuclear effects

- Dutta

- Smirnov

- 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

*muon*

*electron*

*tau*

*monopole*

## 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**=0.01*

*v**cut**=10**-4*

*v**cut**=10**-4*

*E**low**=10 TeV*

## Algorithm errors: average propagation

*Deviation from average energy loss (with v**cut**=1)*
*Propagating 4 10**6** 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*

*MUM*

*LOH*

*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

*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