1. CORSIKA/MMC for the IceCube simulation production
Dmitry Chirkin
University of California at Berkeley, Berkeley, CA 94720, USA
IceCube Detector Simulation workshop, Belgium, October 2003

2. Talk outline generators/propagators – what are they good for?
description of optimizations done for AMANDA-II:
CORSIKA
MMC
conclusions

3. Simulation chain as used in AMANDA
known muon propagators:
MMC
MUM
mudedx
Lip
Loh
generator
step
known air shower
generators:
CORSIKA based
dCORSIKA
pCORSIKA
basiev
propagator
step
Also new possible applications:
CORSIKA => atm. ν generation
Kosta Schinarakis, Wuppertal
MMC => monopole propagation
Peter Niessen, Arvid Pohl

4. CORSIKA settings
6 interaction models, QGSJET, VENUS and NEXUS describe AMANDA-II data best, QGSJET is by far the fastest
Atmosphere and Earth’s surface are curved
Detector is assumed cylindrical

5. Running CORSIKA consists of 2 steps:
CORSIKA (shower generation)
UCR (Utility for CORSIKA output Randomization – shower location randomizer)

6. USER_DEF mmc_en NR E_INI E_CPD E_IN E_OUT CDP_X CDP_Y CDP_Z Z_IN Z_OUT
Running MMC
Basic features:
can propagate muons with fixed vcut or ecut in regions 1
and 2 (use negative values to change default behavior)
propagates muons with up to 1020 eV, can be used up to
1030 eV (enable with “–ebig=1.e21” flag)
can propagate muons and/or taus. To propagate both,
run MMC for taus first, then pipe into MMC for muons
Can propagate muons though multiple media with
spherical or flat interfaces. For concentric media uses
external file with media location definitions
User line can be enabled for each muon. To ensure
compatibility with other AMANDA software, use
“-rdmc” (for f2k) and/or “-amasim” (for AMASIM)
provides multiple output formats (3 at the moment)
Vcut=0.05, 0.01, 10-3 and 10-4
Usual (no cont) vs. cont option
Defalt values used for AMANDA:
vcut=0.05, cont
ecut=500 MeV no cont
vcut=1.0 no cont
User line definition:
USER_DEF mmc_en NR E_INI E_CPD E_IN E_OUT CDP_X CDP_Y CDP_Z Z_IN Z_OUT

7. MMC optimizations cont.
Interpolation routines and strategy of their use have been heavily optimized
Parameterization and interpolation settings can be easily reconfigured (e.g. with “-g=[romberg]” option at run time or with “-hifi” option during compilation)
Algorithm works to the extreme: tested up to the muon energy of 1030 eV and vcut as low as

8. Conclusions and dicussion
CORSIKA and MMC have been heavily optimized
Please note that some optimization settings are AMANDA-II specific and need to be recalculated for desired IceCube geometry