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TeV CR composition with GLAST Guido Barbiellini, Valter Bonvini, Mirko Boezio, Francesco Longo, Andrea Vacchi University and INFN, Trieste, Italy guido.barbiellini@ts.infn.it A.Deangelis et al. University of Udine and INFN, Trieste G.Busetto et al., University and INFN Padova
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TeV CR compositionwith GLAST Guido Barbiellini, Valter Bonvini, Mirko Boezio, Francesco Longo, Andrea Vacchi University and INFN, Trieste, Italy guido.barbiellini@ts.infn.it A.Deangelis et al. University of Udine and INFN, Trieste G.Busetto et al., University and INFN Padova P.Spinelli et al., University and INFN, Bari …
Brief introduction CR spectrum at the knee ACCESS CR measurements at TeV The concept (NUCLEON proposal) Preliminary calculations Events per day with GLAST Outline
Emax ~ bshock Ze x B x Rshock Emax ~ Z x 100 TeV with exponential cutoff of each component But spectrum continues to higher energy: Emax problem SNR shock acceleration
Differential spectral index changes at ~ 3 x 1015eV a = 2.7 a = 3.0 Continues to 3 x 1018 eV Expect exp{-E / Z Emax} cutoff for each Z Fine-tuning problem: To match smoothly a new source with a steeper spectrum Knee of spectrum Knee
Total protons Fe helium CNO Mg… Speculation on the knee 1 1 Component: a = 2.7, Emax = Z x 30 TeV; Emax = Z x 1 PeV 3 components a=2.7 a=2.4 K-H Kampert et al., astro-ph/0204205
Access • Element identifier dimensions: 2m x 2m x 0.3m • Silicon solid state detector array 4 layers • Aerogel Cherenkov detector • Plastic Cherenkov detector • Scintillating optical fiber hodoscope • Relativistic velocity identifier dimensions: 1.7m x 1.7m x 1.2m • Transition radiation (TR) detector composed of • 6 layers of TR radiating blankets • 12 layers of Xe filled proportional tubes • Energy identifier dimensions: 1m x 1m x 0.8m • One interaction length of carbon target • 30 radiation lengths of BGO (Bismuth germanate scintillator)
NUCLEON G.Bashindzhagyan et al. ICRC 2003
NUCLEON tests G.Bashindzhagyan et al. ICRC 2003
NUCLEON tests G.Bashindzhagyan et al. ICRC 2003
NUCLEON simulation A.N. Turundaevsky et al. ICRC 2003
GLAST for CR? • CR spectrum: • GLAST surface : ~3m2 • Solid Angle: ~ 2 steradians • Energy of 1 event per day (with optimal efficiency) • Energy of 1 event per 100 days (with optimal efficiency)
Work in progress • The concept • Charge by dE/dx before interaction • Energy deposit and secondary transverse profile after interaction • GLAST simulation • G3 preliminary (with CR interaction) • G4 full with trigger • Test Beam evaluation • Caveats • Efficiency • Electronics