LHC-Collider Physics and Simulation for High Energy Cosmic Rays J. N. Capdevielle, APC, University Paris Diderot firstname.lastname@example.org
Outline • General properties of giant EAS • The extrapolation at UHE • The treatment of inclined GAS in AGASA • The treatment of the vertical energy estimator • Amendments of experimental data and general convergence to GZK prediction • Mass composition at UHE
Hybrid approach to the primary cosmic ray composition R. Attallah1 and J.N. Capdevielle2 1Physics Department, Univ. of Annaba, Algeria 2APC, Univ. of Paris 7, France
Introduction • The chemical composition of primary cosmic rays furnishes crucial clues on their sources; • A direct measurement of their high energy component runs out of statistics; • Above 1014 eV, observation must resort to indirect method (air shower measurements);
Chemical composition • Air shower interpretation is hampered by our lack of knowledge of the particle interaction physics; • Air showers present very large fluctuations; • Classic air shower experiments only sample the air shower at one depth. • Extensive fitting and interpolation are needed.
A novel technique by IACT • Ground-based detection of the Direct Cherenkov (DC) light emitted by the primary particle; • The intensity of this light is proportional to Z 2; • Measurement of the energy spectrum for cosmic ray nuclei in the range 13-200 TeV (H.E.S.S.); • Limited energy window.
Hybrid detector • DC-light detection can be combined with a classic air shower experiment in order to measure on an event-by-event basis: 1. the mass and energy of the primary particle; 2. the particle content of the shower; • to test experimentally the different critera used for the identification of primary cosmic rays. • to approach the elemental composition around the knee with validated criteria.
Monte Carlo calculations • CORSIKA package v. 6.617 (Heck et al. 1998). • Two independant high energy hadronic interaction models: 1. QGSJET v. II-03 (Ostapchenko 2006) 2. SIBYLL v. 2.3 (Engel et al. 1999). • Fluka model v. 2005 at low energy (Ferrari et al. 2005).
Experimental conditions • Primary particles considered: p, N, Fe (vertical). • Primary energy: 50 TeV and 200 TeV • Observation level at H.E.S.S. altitude (1830 m; 830.5 g/cm2). • Detection energy thresholds: E 300 MeV, Ee 2 MeV • 100 showers per run.
Conclusion • DC-light detection can be combined with a classic air shower experiment. • Such a hybrid detector is able to test the different criteria used for primary cosmic ray identification. • Validated criteria can be used to study the cosmic ray compostion around the knee.
Total p-p Cross-Section ~ ln2 s • Current models predictions: 90-130 mb • Aim of TOTEM: ~1% accuracy COMPETE Collaboration fits all available hadronic data and predicts: LHC: [PRL 89 201801 (2002)]
non-diffractive minimum bias events Acceptance dNch/dh [1/unit] Energy(GeV) per event Charged particles per event = - ln tg single-diffractive events All detectors with trigger capability Trigger acceptance > 95% for all inelastic events
Concorde Fox Charlie, Roissy, Octobre 78 Une centaine d’AR Paris New York pour exposer à 17000m d’altitude deux chambres à émulsion (pendant 270H).
Chambers for Balloon and Airborne Experiments • Evis=E(h)+E • Energy threshold • Stratospheric 200 GeV • Mountain altitude 2-4 TeV • Particle physics observed in XREC • - n, E, <r>, < E r> • nch, EH, <rH>, < EH rH> • - Energy and PT distributions • - pseudorapidity distributions • - dN/d=f() • - correlations <PT>, dN/d • (more or less completely) • - direct interaction in the chambers • - near direct interactions with • localized origin
CERN Courier Octobre 1981 • Début des expériences Octobre 1978 • Une collision de 106 GeV (forte multiplicité, spikes dans la distribution de pseudo-rapidité)
Chambres à émulsion sur Concorde • Impact d ’un photon de 200 TeV, l ’un des 211 g d ’une collision de 107 GeV. • Evènement à émission coplanaire. • 50ch sur A80 5000H • 500 p 1PeV, 7 10 PeV • 250 familles g , 10 PeV , 3 au LHC (100 PeV)
Xray film under 8 c.u. Lego plot with the 4 most energetic Gamma ’s JF2af2 (Concorde)
Jf2af2 (Concorde) • 34 g ’s aligned • about 50% of the visible energy
One possible configuration • External ’s and total <ER> factors indicate a common origin under 2.2km above the chamber • Like in Strana, we need pt ‘ s > 10 GeV/c for the emission of 3 high energy hadrons generating A, Ap, B • Threshold energy for valence quarks in alignment ~200 GeV in c.m.s.(proton of 1016 eV in Lab)
Most energetic events above LHC energy • Tadjikistan • Andromeda • Fianit • normal hadron and g ’s content reproduced with CORSIKA (1500 g ’s in Fianit, but few chances to reproduce the 10 PeV g ’s in the halo)
Comment • Coplanar emission , even if partly explained by fluctuations, needs more attention • p-A and A-A collisions have to be considered, for peripheral collisions (RHIC results) to point out QGP signatures in spikes or very large Pt .Semi inclusive data consequences may be important • New experiements(LHC energy, forward region) with emulsion bricks can be performed with air cargo liners and at mountain altitude