CORSIKA: Extensive Simulation

Stefan Klepser

DESY Zeuthen, Humboldt-Universität zu Berlin

dec 2006 Outline

• CORSIKA basics – introduction –workflow –thecode – steering a simulation

• Interaction Models

• CORSIKA in I3

ۻ Special Effects • – curved & upward option – LPM-Effect – ν-induced Showers

Stefan Klepser, DESY Zeuthen: CORSIKA 2/25 Extensive Air Shower Basics

Energy flow:

Stefan Klepser, DESY Zeuthen: CORSIKA 3/25 CORSIKA Task Flow

Stefan Klepser, DESY Zeuthen: CORSIKA 4/25 The Corsika Code...

All code except interaction models & root output is in 1 fortran file corsika.F:

–2 MB – 61882 lines – 11444 comment lines 234 lines / substructure – 54 functions – 210 subroutines

Stefan Klepser, DESY Zeuthen: CORSIKA 5/25 Simulation: Features

• Input Features: • Output Features:

– Primary Particle Parameters: – Secondary Particle Information: • Type: γ, p, He, O, Fe, μ, ν... • Type: γ, p, He, O, Fe, μ, ... • Energy: single or spectrum • Energy • Direction: single or area • Direction • Position – Surrounding Parameters: •Time • Atmosphere • Earth‘s Magnetic Field – Longitudinal & Lateral Distributions: • Detection height (multiples oplto options Compilation • Energy possible) • Particle Number

Steering file options – Simulation Parameters: – Statistical Collision Information • Interaction models • Energies •Thinning • Number of Secondaries • Energy Thresholds • Curved Atmosphere Option • Multiplicity • Upward Option –Specials • LPM, Preshower • , Cherenkov Tracking • • Cherenkov-Light • Fluorescence Light Stefan Klepser, DESY Zeuthen: CORSIKA 6/25 The Input File

run corsika on command line:

~ % cd $CORSIKA/run # yes, neccessary ~ % corsika6502Linux_SIBYLL_fluka < input.inp > output.out

to get

DAT000001 (binary) or DAT000001.root

Stefan Klepser, DESY Zeuthen: CORSIKA 7/25 photon proton iron Sketches of different showers... 1014 eV 1014 eV 1014 eV

red = , positrons, gammas green = muons blue =

Energy cuts: 0.1 MeV for e+-, gammas 0.1 GeV for muons, hadrons

Stefan Klepser, DESY Zeuthen: CORSIKA 8/25 Sketches of single components – proton shower

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

Stefan Klepser, DESY Zeuthen: CORSIKA 10/25 Interaction models

Stefan Klepser, DESY Zeuthen: CORSIKA 11/25 Electromagnetic Interactions: EGS4

• ‚EGS‘ = 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 > 1018eV)

→ NO PROBLEM HERE!

Stefan Klepser, DESY Zeuthen: CORSIKA 12/25 Hadronic Interactions default „ high“/„low“ energy Energy ranges:

• resonance range • intermediate range • high-energy range transition

Stefan Klepser, DESY Zeuthen: CORSIKA 13/25 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 isnot updated anymore! It should not be used any longer!

Stefan Klepser, DESY Zeuthen: CORSIKA 14/25 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 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 CORSIKA in I3

• simulation doxygen: http://software.icecube.wisc.edu/SIMULATION/

• production homepage: http://icecube.wisc.edu/simulation/

Stefan Klepser, DESY Zeuthen: CORSIKA 17/25 InIce CORSIKA in I3

• Module Flow:

I3Muxer → I3GeneratorUCR → I3PropagatorMMC → ...

r w a e p r ( n a ( r a b b o d d p y y p s p D p D a i e r n g . o . r C C a p f f i t h l h o a e e i i r r g s r s k a k t m h i g i n t n e e e ) ) u s n j o a t e n h v r s a e a m t t e h p d r r t o o h w u g r r o i g t a u h h m g s t h h t m a e t h n m d e d e c a , p t l e l o a c n n t e o e r t d C O

R S I K A

Stefan Klepser, DESY Zeuthen: CORSIKA 18/25 IceTop CORSIKA in I3

• Module Flow:

I3Muxer → I3CorsikaXX → I3ArrayShowerTracer → I3Romeo...

r c a e b a ( n a ( y l b b c d d y y t u s h l P p P a i e u n . . t i e t n N s p N s l t i t a i e e h e t r h ß i ß e n s e e e e p C n n c t a a O ) t / n r o t R k A i f c . S t s l e h i O I g s K e l n i i A v n p a

a f a l t i s l r f h e t o ) i e s c r l f e e r a a t m r c a h e c k p a w r t i i t c h l e t h e

t a n k

Stefan Klepser, DESY Zeuthen: CORSIKA 19/25 Special Effects

• Curved & Upward option

• LPM-Effect

• Neutrino-Induced Showers

Stefan Klepser, DESY Zeuthen: CORSIKA 20/25 Curved & Upward options for inclined showers (e.g. neutrino showers)

h

standard curved upward

Stefan Klepser, DESY Zeuthen: CORSIKA 21/25 LPM-Effect

• ‚LPM‘ = Landau-Pomeranchuk-Migdal • effect on high energy gammas > 1018 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 Confusing HE showers...

Preshower UHE p-shower ~ HE γ-shower! LPM → some UHE Events could have been photons!

Stefan Klepser, DESY Zeuthen: CORSIKA 23/25 Neutrino-Induced Showers

• CORSIKA + HERWIG (O. Pisanti et al.) = ν-induced shower • Mostly horizontally possible (ν + air, mountain) → curved & upward option! • Different signatures:

ν μ→NO shower νe νe μ

N * N N* → shower N → shower

ν τ→decay → shower νe e → shower τ

N * N N* → shower N → shower double bang Stefan Klepser, DESY Zeuthen: CORSIKA 24/25 Summary

• The talk was great • Everything is clear

Stefan Klepser, DESY Zeuthen: CORSIKA 25/25 Resonance Range

All kinds of occuring resonances, well-measured in experiments, are taken into account:

PDG

Stefan Klepser, DESY Zeuthen: CORSIKA 26/25 Intermediate Range

QCD String fragmentation processes:

i) inelastic, with gluon radiation ii) elastic, diffraction dissociation

Stefan Klepser, DESY Zeuthen: CORSIKA 27/25 High-Energy Range

• Hard Physics (high pt = „easy“): QCD → Minijet Production, ...

• Soft Physics (low pt = „difficult“): Gribov-Regge-Theory = Treating Parton Cascades as Quasi-Particles

→ POMERON (named after Isaak Yakovlevich Pomeranchuk)

==

Stefan Klepser, DESY Zeuthen: CORSIKA 28/25 QGSJET-II

Semi-hard processes:

(Sergej Ostapchenko)

Stefan Klepser, DESY Zeuthen: CORSIKA 29/25