Presentation on theme: "Hybrid Extensive Air Shower Detector Array at the University of Puebla to Study Cosmic Rays O. MARTINEZ, H. SALAZAR, L. VILLASEÑOR * + Grupo de Estudiantes."— Presentation transcript:
Hybrid Extensive Air Shower Detector Array at the University of Puebla to Study Cosmic Rays O. MARTINEZ, H. SALAZAR, L. VILLASEÑOR * + Grupo de Estudiantes Facultad de Físico-Matemáticas, Benemérita Universidad Autónoma de Puebla, Apartado Postal 1364, Puebla, Pue., 72000, México *On leave of absence from Institute of Physics and Mathematics, University of Michoacan, Morelia, Mich., 58040, México EMA 05 Morelia July 18-22, 2005
MPV of EM peak = 0.12 VEM i.e. around 29 MeV, i.e., dominated By knock-on + decay electrons
Stopping muon at 0.1 VEM Decay electron at 0.17 VEM = 41 MeV Crossing muon at 1 VEM Alarcón M. et al., NIM A 420 [1-2], 39-47 (1999).
Data Analysis Arrival direction sin sin = d/c(t 2 -t 1 )
Angular distribution inferred directly from the relative arrival times of shower front in good agreement with the literature: cos p sen
Data Analysis Lateral Distribution Functions Energy Determination EAS-TOP, Astrop. Phys, 10(1999)1-9 The shower core is located as the center of gravity.
N e, obtained for vertical showers. The fitted curve is I k (N e /N ek ) - , gives =2.44±0.13 which corresponds to a spectral index of the enerfy distributions of =2.6
Cherenkov Liquid Scint Muons deposit 240 MeV in 1.20m high water and only 26 MeV in 13 cm high liquid, while electrons deposit all of their energy i.e., around 10 MeV. Therefore for 10 Mev electrons we expect: Mu/EM=24 for Cherenkov Mu/EM=2.6 for Liq. Scint. Muon/EM Separation
Iterations Start with Ne=82,300 Nmu = 32700 E0 = 233 TeV Iterations End with Ne=68000 Nmu = 18200 E0 = 196 TeV
Mass Composition Non-Hybrid Array Do a three parameter fit to :
Mass Composition Non-Hybrid but Composite Array Two Identical types of Cherenkov Detectors one filled with 1.20 m of water and the other with 0.60 m, i.e., VEM C’ =0.5VEM C i.e., do independent fits of EM and muon to NKG and Greissen LDF, respectively, where:
Conclusions We have checked the stability and performed the calibration of the detectors. We have measured and analyzed the arrival direction of showers. We determine the energy of the primary by measuring the total number of charged particles obtaining by integration of the fitted LDF. Study of Muon/Electromagnetic ratio is underway: