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تسجيل مستخدم جديدSignatures of Protons in UHECR
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We demonstrate that the energy spectra of Ultra High Energy Cosmic Rays (UHECR) as observed by AGASA, Flys Eye, HiRes and Yakutsk detectors, have the imprints of UHE proton interaction with the CMB radiation as the dip centered at $Esim 1times 10^{19}$ eV, beginning of the GZK cutoff, and very good agreement with calculated spectrum shape. This conclusion about proton composition agrees with recent HiRes data on elongation rate that support the proton composition at $Egeq 1times 10^{18}$ eV. The visible bump in the spectrum at $E sim 4times 10^{19}$ eV is not caused by pile-up protons, but is an artifact of multiplying the spectrum by $E^3$. We argue that these data, combined with small-angle clustering and correlation with AGN (BL Lacs), point to the AGN model of UHECR origin at energies $E leq 1times 10^{20}$ eV. The events at higher energies and the excess of the events at $E geq 1times 10^{20}$ eV, which is observed by AGASA (but absent in the HiRes data) must be explained by another component of UHECR, e.g. by UHECR from superheavy dark matter.
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We demonstrate that the energy spectra of Ultra High Energy Cosmic rays (UHECR) as observed by AGASA, Flys Eye, HiRes and Yakutsk detectors, have the imprints of UHE proton interaction with the CMB radiation in the form of the dip at $Esim 1times 10^
{19}$~ eV, of the beginning of the GZK cutoff, and of very good agreement with calculated spectrum shape. We argue that these data, combined with small-angle clustering and correlation with AGN (BL Lacs), point to the AGN model of UHECR origin at energies $E lsim 1times 10^{20}$ eV. The excess of the events at $E gsim 1times 10^{20}$ eV, which is observed by AGASA (but absent in HiRes data) can be explained by another component of UHECR, e.g. by UHECR from superheavy dark matter.
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There will be a review of the history of polarized proton beams, and a discussion of the unexpected and still unexplained large transverse spin effects found in several high energy proton-proton spin experiments at the ZGS, AGS and Fermilab. Next, th
ere will be a discussion of present and possible future experiments on the violent elastic collisions of polarized protons at the 70 GeV U-70 accelerator at IHEP-Protvino in Russia and the new high intensity 50 GeV J-PARC facility being built at Tokai in Japan.
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