Observation of the Ankle and Evidence for a High-EnergyBreak in the Cosmic Ray Spectrum
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چکیده
Preprint submitted to Elsevier Science 17 December 2004 We have measured the cosmic ray spectrum at energies above 1017 eV using the two air fluorescence detectors of the High Resolution Fly’s Eye experiment operating in monocular mode. We describe the detector, PMT and atmospheric calibrations, and the analysis techniques for the two detectors. We fit the spectrum to models describing galactic and extragalactic sources. Our measured spectrum gives an observation of a feature known as “the ankle” near 3 × 1018 eV, and strong evidence for a supression near 6 × 1019 eV.
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تاریخ انتشار 2004