target a hadronic interaction model for studying inclusive muon and neutrino fluxes
DESCRIPTION
TARGET A hadronic interaction model for studying inclusive muon and neutrino fluxes. Ralph Engel (Forschungszentrum Karlsruhe, Germany) Giles Barr, Thomas K. Gaisser, Simon Robbins and Todor Stanev. Motivation and outline. TARGET 3D (old version: 2.1, current version: 2.4) - PowerPoint PPT PresentationTRANSCRIPT
TARGET
A hadronic interaction model for studying inclusive muon and
neutrino fluxes
Ralph Engel (Forschungszentrum Karlsruhe, Germany)
Giles Barr, Thomas K. Gaisser, Simon Robbins and Todor Stanev
Motivation and outline
TARGET 3D (old version: 2.1, current version: 2.4)
very flexible and tunable hadronic interaction model
simple and fast Monte Carlo code
optimization for inclusive muon/neutrino fluxes
event generation structure and recent improvements
comparison to data
application: L3+C muon flux Ralph Engel, ICRC 2003
Event generation in TARGET simulation of one proton-air interaction
event type
leading particle (projectile)
nucleons from target nucleus
fast pions and kaons (correlated with leading particle)
slow pions and kaons (correlated with target nucleons)
baryon-antibaryon pair production
central pion and kaon production
multiplicity determined by energy conservation
cross sections: PDG data and Glauber approachRalph Engel, ICRC 2003
Event generation in TARGET simulation of one proton-air interaction
event type
leading particle (projectile)
nucleons from target nucleus
fast pions and kaons (correlated with leading particle)
slow pions and kaons (correlated with target nucleons)
baryon-antibaryon pair production
central pion and kaon production
multiplicity determined by energy conservation
cross sections: PDG data and Glauber approachRalph Engel, ICRC 2003
Nucleons: projectile/target fragmentation
old version:
no target fragmentation nucleons
tuned to Eichten et al. data
data converted from double-differential cross sectionsRalph Engel, ICRC 2003
Nucleons: projectile/target fragmentation
new version:
target fragmentation nucleons
target and projectile nucleons symmetric
Ralph Engel, ICRC 2003
Nucleons: comparison to other models
large differences between models
inconsistent data
not very important for flux calculations
Ralph Engel, ICRC 2003
(Gaisser & Honda, Ann. Rev. Nucl. Part. Sci. 52 (2002) 153)
Low-energy pion production (1)
Ralph Engel, ICRC 2003
full phase space measurement
recoil nucleons change energy available for particle production
Low-energy pion production (2)
Ralph Engel, ICRC 2003
full phase space measurement
slow pions from fragmentation of target nucleons
Low-energy pion production (3)
Ralph Engel, ICRC 2003
full phase space measurement
pion multiplicity at small x too high?
Baryon-antibaryon pair production
Ralph Engel, ICRC 2003
no data for nuclear targets
scaled p-p cross sections and distributions used
production of anti- protons, neutrons and lambdas
Comparison with p-Be at 24 GeV (1)
Ralph Engel, ICRC 2003
almost no change of distributions at higher energy
Comparison with p-Be at 24 GeV (2)
Ralph Engel, ICRC 2003
almost no change of distributions at higher energy
Comparison to L3+C muon measurement
Ralph Engel, ICRC 2003
TARGET predictions: good description of L3+C data
SIBYLL gives similarly good description
QGSjet: too few fast pions
(see talks by M. Unger, HE 2.1.10 and T. Stanev, HE 2.4.9)
Comparison of high-energy models
inclusive charged pion spectra
p-air collisions, Elab = 500 GeV
fast pions very important
Ralph Engel, ICRC 2003
Summary and outlook
Ralph Engel, ICRC 2003
TARGET: simple and very flexible event generator
version 2.4:
implementation of processes needed for comparison to forthcoming HARP/NA49 data
improved description of low-energy data
minor changes at high energy
plans: additional fine-tuning and release of new version
Pions: comparison to other models
large differences between models at low and high x
some data sets inconsistent
very important for flux calculations
Ralph Engel, ICRC 2003
(Gaisser & Honda, Ann. Rev. Nucl. Part. Sci. 52 (2002) 153)
Muon flux charge ratio
charge ratio very sensitive to leading particle production
slightly too many fast neg. pions in new version of TARGET
fine-tuning in progress
Ralph Engel, ICRC 2003