1

Update on Corsika Simulation29 June 2015

Fabrizio Coccetti

2

Choice of Models for Hadronic Interactions

• After talking with experts (Lorenzo Perrone and Daniele Martello), we decided which models should be used to generate showers for EEE:– High-energy Hadronic Interactions:

EPOS (this is the only model available in Corsika which reproduces heavy ion data from RHIC *and* LHC )

– Low-energy Hadronic Interactions: FLUKA (standard choice)

3

Configuration

EPOS Parameters

EPOPAR input ../epos/epos.param !initialization input file for eposEPOPAR fname inics ../epos/epos.inics !initialization input file for eposEPOPAR fname iniev ../epos/epos.iniev !initialization input file for eposEPOPAR fname initl ../epos/epos.initl !initialization input file for eposEPOPAR fname inirj ../epos/epos.inirj !initialization input file for eposEPOPAR fname inihy ../epos/epos.ini1b !initialization input file for eposEPOPAR fname check none EPOPAR fname histo none EPOPAR fname data none EPOPAR fname copy none

4

Configuration

Energy Cuts (Same as ARGO)

ECUTS 0.05 0.05 0.00005 0.00005

(GeV)Hadrons, Muons, Electrons, Photons The low energy cut-off of the particle kinetic energy

5

Configuration

Observation Level (Sea level)

OBSLEV 0.E2

(cm)

6

Configuration

magnetic field (Rome)

MAGNET 24.5 39.4

24.5: is the horizontal component of the Earth’s magnetic field (in μT) to the x-direction of the detector (North)39.4: is the vertical component of the Earth’s magnetic field (in μT) downwards.

7

e3sim is a python package written to perform simulations for the (Extreme Energy Events) EEE experiment. Available on:github.com/centrofermi

The software can also convert the Fortran Binary Files (standard output of Corsika) to ROOT files.

A python package to use Corsika to generate showers at CNAF

8

Extensive Air Shower generation and conversion at CNAF

• Thousands (details in next slides) of EASs have been generated at CNAF via the python wrapper “e3sim”.

• The Fortran Binaries Files (standard output of Corsika) can be found on the analysis machines at CNAF in /MC/

• I am converting all files into ROOT Trees, which can be found on the analysis machines at CNAF in /MC/root/

• Subfolders are named by the energy of the primary in GeV.

9

EAS generated and converted in ROOT format at CNAF (situation on June 26, 2015)

Energy of the

primary (GeV)

Number of showers

available in binary

Number of showers

converted in root

103 10000 10000

5 x 103 10000 (**)

104 2000 2000

5 x 104 2000 (**)

105 1000 1000

5 x 105 235(*) (**)

106 20 20

5 x 106 10 (**)

107 10 10

KEY ASPECTS:Primaries are protonsObservation Level: 0 mMagnetic Field: RomeHigh-energy Hadronic Interactions: EPOSLow-energy Hadronic Interactions: FLUKA

Each shower is identified by a unique number(which is also the seed of the random numbers generator)[I will provide a table of these numbers]

(*) generation in progress(**) conversion in progress

10

One example• Let’s have a look at a Cosmic Ray Shower generated

by a proton of 107 GeV• Location of these kind of showers at CNAF:

“/MC/root/10000000/”• It takes ~1 day of CPU time to generate one of these

showers (10 available at the moment). • Let’s consider the shower: DAT450000.root• All information about the generation of this specific

shower are in (txt format):– /MC/10000000/output-450000– /MC/10000000/input-450000

11

Let’s look at some variables of the Root Tree

• Let’s look at a part of the tree of DAT450000.root– shower.EventID = 450000 (unique number of the event)

– shower.Energy = 1e+07 (energy of the primary in GeV)

– shower.Theta = 0.7927 (theta of the primary in radian)

– shower.Phi = -0.2731 (Phi of the primary in radian)

– shower.nPhotons = 1203306 (number of Photons at the ground level)

– shower.nElectrons = 115897 (number of Electrons at the ground level)

– shower.nHadrons = 6582 (number of Hadrons at the ground level)

– shower.nMuons = 48772 (number of Muons at the ground level)

– Also available: full particle IDs, times since first interaction…– All characteristics of the shower are stored in the tree (i.e. magnetic

field ,energy cuts, models). Full documentation will soon be on github.– Coordinates and Momenta (px, py, pz) at observation level are available for

each particle in particle..x and particle..y

12

Just an example: Muons density at ground level for DAT450000.root

Please note that Corsika writes coordinates in cm (!!)

12 km

12 km

Primary:Proton 107 GeV

Note: in ParticleID, 5 selects μ+ and 6 selects μ-

13

What’s next

• Generate more showers with this configuration (Note: Collaboration should decide the numbers for each energy)

• Generate showers where the primary is not a proton (everything is ready)

• Increase the energy level (in this case, experts working at Karlsruhe said we need to change the input parameters of the models, I will discuss with them again)

• Generate sets of showers with different configurations (in particular: Observation Level and Magnetic Field)