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Contemporary Physics, 2010
Ultra High Energy Cosmic Rays (UHECRs) represent the most energetic source of elementary particles available to scientists. They have macroscopic energies, exceeding 5 × 1019 eV, and as yet unidentified sources. Unfortunately, their flux is as low as one particle per century per square kilometre, requiring dedicated detectors with huge apertures to ...
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Ultra High Energy Cosmic Rays (UHECRs) represent the most energetic source of elementary particles available to scientists. They have macroscopic energies, exceeding 5 × 1019 eV, and as yet unidentified sources. Unfortunately, their flux is as low as one particle per century per square kilometre, requiring dedicated detectors with huge apertures to ...
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Ultra high energy cosmic ray horizons
Nuclear Physics B - Proceedings Supplements, 2009We calculate the horizons of ultra high energy cosmic rays assuming different primary nuclei ranging from proton to iron at ultra high energies ( 6 ⋅ 10 19 eV ). We show that sources of ultra high energy protons and heavy nuclei can originate from distances up to ∼ 180 Mpc , while low and intermediate mass nuclei can only originate
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Nuclear Physics B - Proceedings Supplements, 2001
Abstract The evidence for the existence of cosmic rays with energies in excess of 1020 eV is now overwhelming. There is so far no indication of the GZK cutoff in the energy spectrum at 5 × 1019 eV. This conclusion is not firm for lack of statistics. A cutoff would be expected if the sources of the cosmic rays were distributed uniformly throughout the
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Abstract The evidence for the existence of cosmic rays with energies in excess of 1020 eV is now overwhelming. There is so far no indication of the GZK cutoff in the energy spectrum at 5 × 1019 eV. This conclusion is not firm for lack of statistics. A cutoff would be expected if the sources of the cosmic rays were distributed uniformly throughout the
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The Puzzle of the Ultra-High Energy Cosmic Rays
International Journal of Modern Physics A, 2002In early years the cosmic ray studies were ahead of the accelerator research, starting from the discovery of positrons, through muons, to that of pions and strange particles. Today we are facing the situation that the puzzling saga of cosmic rays of the highest energies may again unfold in the discovery of new physics, now beyond the Standard Model ...
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Ultra high energy cosmic rays and ultra high energy γ-rays
Advances in Space Research, 1984Abstract Evidence on the energy spectrum, mass composition and anisotropy of cosmic rays above 10 14 eV is briefly surveyed and it is shown that the data are consistent with all cosmic rays below 10 19 eV being of galactic origin. Results from the new field of γ-ray astronomy above 10 15 eV are described and implications for the origin of cosmic ...
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Ultra high energy cosmic ray (present)
Nuclear Physics B - Proceedings Supplements, 2002Abstract The existence of Super-GZK particles, cosmic rays above 10 20 eV , was well established by the AGASA experiment. Recent data from AGASA strongly suggests the existence of compact sources, event clusters. These two experimental evidences seem to be contradictory each other and are difficult to be explained by the simple theoretical models ...
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1983
The interpretation of observations on cosmic rays above 1015 eV is discussed in simple terms, without considering detailed models. The variation of the amplitude of anisotropy with energy (compared with a “leaky box” picture) and the anisotropy in galactic latitude (indicating a local density gradient) strongly suggest a galactic origin for particles ...
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The interpretation of observations on cosmic rays above 1015 eV is discussed in simple terms, without considering detailed models. The variation of the amplitude of anisotropy with energy (compared with a “leaky box” picture) and the anisotropy in galactic latitude (indicating a local density gradient) strongly suggest a galactic origin for particles ...
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On origin of ultra high energy cosmic rays
Astrophysics and Space Science, 2007Propagation of UHE protons through CMB radiation leaves the imprint on energy spectrum in the form of Greisen–Zatsepin–Kuzmin (GZK) cutoff, bump (pile-up protons) and dip. The dip is a feature in energy range 1×1018–4×1019 eV, caused by electron-positron pair production on CMB photons.
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The Origin of Ultra-High-Energy Cosmic Rays
Annual Review of Astronomy and Astrophysics, 1984openaire +2 more sources