CORSIKA: Extensive Air Shower Simulation

Transcription

1 CORSIKA: Extensive Air Shower Simulation Stefan Klepser DESY Zeuthen, Humboldt-Universität zu Berlin dec 2006

2 Outline CORSIKA basics introduction work flow the code steering a simulation Interaction Models CORSIKA in I3 Special Effects ۻ curved & upward option LPM-Effect ν-induced Showers Stefan Klepser, DESY Zeuthen: CORSIKA 2/25

3 Extensive Air Shower Basics Energy flow: Stefan Klepser, DESY Zeuthen: CORSIKA 3/25

4 CORSIKA Task Flow Stefan Klepser, DESY Zeuthen: CORSIKA 4/25

5 The Corsika Code... All code except interaction models & root output is in 1 fortran file corsika.f: 2 MB lines comment lines 54 functions 210 subroutines 234 lines / substructure Stefan Klepser, DESY Zeuthen: CORSIKA 5/25

6 Simulation: Features Input Features: Output Features: Steering file options Primary Particle Parameters: Type: γ, p, He, O, Fe, μ, ν... Energy: single or spectrum Direction: single or area Surrounding Parameters: Atmosphere Earth s Magnetic Field Detection height (multiples possible) Simulation Parameters: Interaction models Thinning Energy Thresholds Curved Atmosphere Option Upward Option LPM, Preshower Neutrino, Cherenkov Tracking Compilation options Secondary Particle Information: Type: γ, p, He, O, Fe, μ,... Energy Direction Position Time Longitudinal & Lateral Distributions: Energy Particle Number Statistical Collision Information Energies Number of Secondaries Multiplicity Specials Neutrinos Cherenkov-Light Fluorescence Light Stefan Klepser, DESY Zeuthen: CORSIKA 6/25

7 The Input File run corsika on command line: ~ % cd $CORSIKA/run # yes, neccessary ~ % corsika6502linux_sibyll_ fluka < input.inp > output.out to get DAT (binary) or DAT root Stefan Klepser, DESY Zeuthen: CORSIKA 7/25

8 photon proton Sketches of different 1014 ev 1014 ev iron showers ev red = electrons, positrons, gammas green = muons blue = hadrons Energy cuts: 0.1 MeV for e+-, gammas 0.1 GeV for muons, hadrons Stefan Klepser, DESY Zeuthen: CORSIKA 8/25

9 Sketches of single components proton shower Stefan Klepser, DESY Zeuthen: CORSIKA 9/25

10 Sketches of single components photon shower Stefan Klepser, DESY Zeuthen: CORSIKA 10/25

11 Interaction models Stefan Klepser, DESY Zeuthen: CORSIKA 11/25

12 Electromagnetic Interactions: EGS4 EGS = Electron Gamma Shower Code 4 = 4-dimensional simulation ALL known e+- and γ interactions are included: bremsstrahlung ionisation d-electrons Bhabha & Moeller scattering multiple scattering annihilation e+e- pair production Compton effect photo effect Rayleigh scattering Extended by the LPM-Effect (relevant in the atmosphere > ev) NO PROBLEM HERE! Stefan Klepser, DESY Zeuthen: CORSIKA 12/25

13 Hadronic Interactions default high / low energy transition Energy ranges: resonance range intermediate range high-energy range Stefan Klepser, DESY Zeuthen: CORSIKA 13/25

14 Recommended LE Models: FLUKA + works best and fastest + always updated due to commercial motivation (NASA,...) - non-open source non-transparent UrQMD (M. Bleicher et al.) + real space-time-simulation + frequently enhanced - slower Note: GHEISHA is not updated anymore! It should not be used any longer! Stefan Klepser, DESY Zeuthen: CORSIKA 14/25

15 Recommended HE Models: QGSJET-II + highly sophisticated Pomeron-Pomeron coupling + fits the data best -slow SIBYLL + - different principle + comparable performance + faster Stefan Klepser, DESY Zeuthen: CORSIKA 15/25

16 Standard settings in I3 muon simulation (nov 2006) adopted from dcorsika (D. Chirkin): LE interactions: GHEISHA HE interactions: QGSJet01.c WHY? Stefan Klepser, DESY Zeuthen: CORSIKA 16/25

17 CORSIKA in I3 simulation doxygen: production homepage: Stefan Klepser, DESY Zeuthen: CORSIKA 17/25

18 InIce CORSIKA in I3 Module Flow: I3Muxer I3GeneratorUCR I3PropagatorMMC... wrapper for the java program mmc, propagates muons through the detector (by D.Chirkin) reads in files generated with standalone dcorsika and propagates them through the planet (by D.Chirkin) Stefan Klepser, DESY Zeuthen: CORSIKA 18/25

19 IceTop CORSIKA in I3 Module Flow: I3Muxer I3CorsikaXX I3ArrayShowerTracer I3Romeo... calculates the tank signal for each particle by the intersect of the particle track with the tank (by P. Nießen) reads in plain CORSIKA files and puts the particles in the frame (by P. Nießen / A. Olivas) Stefan Klepser, DESY Zeuthen: CORSIKA 19/25

20 Special Effects Curved & Upward option LPM-Effect Neutrino-Induced Showers Stefan Klepser, DESY Zeuthen: CORSIKA 20/25

21 Curved & Upward options for inclined showers (e.g. neutrino showers) h standard curved upward Stefan Klepser, DESY Zeuthen: CORSIKA 21/25

22 LPM-Effect LPM = Landau-Pomeranchuk-Migdal effect on high energy gammas > ev The multiple Coulomb scattering angle exceeds the [bremsstrahlung] emission cone, so the radiation intensity diminishes That means: bremsstrahlung and pair production decreases with higher energy or denser air high energy gamma showers get even deeper in the atmosphere Stefan Klepser, DESY Zeuthen: CORSIKA 22/25

23 Confusing HE showers... LPM Preshower UHE p-shower ~ HE γ-shower! some UHE Events could have been photons! Stefan Klepser, DESY Zeuthen: CORSIKA 23/25

24 Neutrino-Induced Showers CORSIKA + HERWIG (O. Pisanti et al.) = ν-induced shower Mostly horizontally possible (ν + air, mountain) curved & upward option! Different signatures: ν e ν e ν μ μ NO shower N N * shower N N * shower ν e e shower ν τ τ decay shower N N * shower N N * shower double bang Stefan Klepser, DESY Zeuthen: CORSIKA 24/25

25 Summary The talk was great Everything is clear Stefan Klepser, DESY Zeuthen: CORSIKA 25/25

26 Resonance Range All kinds of occuring resonances, well-measured in experiments, are taken into account: PDG Stefan Klepser, DESY Zeuthen: CORSIKA 26/25

27 Intermediate Range QCD String fragmentation processes: i) inelastic, with gluon radiation ii) elastic, diffraction dissociation Stefan Klepser, DESY Zeuthen: CORSIKA 27/25

28 High-Energy Range Hard Physics (high p t = easy ): QCD Minijet Production,... Soft Physics (low p t = difficult ): Gribov-Regge-Theory = Treating Parton Cascades as Quasi-Particles POMERON (named after Isaak Yakovlevich Pomeranchuk) = = Stefan Klepser, DESY Zeuthen: CORSIKA 28/25

29 QGSJET-II Semi-hard processes: (Sergej Ostapchenko) Stefan Klepser, DESY Zeuthen: CORSIKA 29/25