15 research outputs found

    Anisotropy expectations for ultra-high-energy cosmic rays with future high statistics experiments

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    UHECRs have attracted a lot of attention due to their challengingly high energies and their potential value to constrain physical processes and astrophysical parameters in the most energetic sources of the universe. Current detectors have failed to detect significant anisotropies which had been expected to allow source identification. Some indications about the UHECR composition, which may become heavier at the highest energies, has even put into question the possibility that such a goal could be achieved soon. We investigate the potential value of a new-generation detector, with 10 times larger exposure, to overcome the current situation and make significant progress in the detection of anisotropies and thus in the study of UHECRs. We take as an example the expected performances of the JEM-EUSO, assuming a uniform full-sky coverage with a total exposure of 300,000 km2 sr yr. We simulate realistic UHECR sky maps for a wide range of possible astrophysical scenarios allowed by the current constraints, taking into account the energy losses and photo-dissociation of the UHECRs, as well as their deflections by magnetic fields. These sky maps, built for the expected statistics of JEM-EUSO as well as for the current Auger statistics, as a reference, are analyzed from the point of view of their intrinsic anisotropies, using the two-point correlation function. A statistical study of the resulting anisotropies is performed for each astrophysical scenario, varying the UHECR source composition and spectrum as well as the source density. We find that significant anisotropies are expected to be detected by a next-generation UHECR detector, for essentially all the astrophysical scenarios studied, and give precise, quantitative meaning to this statement. Our results show that a gain of one order of magnitude in exposure would make a significant difference compared to the existing detectors.Comment: 26 pages, 28 figure

    Constraining Supersymmetry using the relic density and the Higgs boson

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    Recent measurements by Planck, LHC experiments, and Xenon100 have significant impact on supersymmetric models and their parameters. We first illustrate the constraints in the mSUGRA plane and then perform a detailed analysis of the general MSSM with 13 free parameters. Using SFitter, Bayesian and Profile Likelihood approaches are applied and their results compared. The allowed structures in the parameter spaces are largely defined by different mechanisms of dark matter annihilation in combination with the light Higgs mass prediction. In mSUGRA the pseudoscalar Higgs funnel and stau co-annihilation processes are still avoiding experimental pressure. In the MSSM stau co-annihilation, the light Higgs funnel, a mixed bino--higgsino region including the heavy Higgs funnel, and a large higgsino region predict the correct relic density. Volume effects and changes in the model parameters impact the extracted mSUGRA and MSSM parameter regions in the Bayesian analysis

    The Pierre Auger Observatory: Contributions to the 33rd International Cosmic Ray Conference (ICRC 2013)

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    The Pierre Auger Observatory: Contributions to the 33rd International Cosmic Ray Conference (ICRC 2013)

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    Interpretation of the depths of maximum of extensive air showers measured by the Pierre Auger Observatory

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    The Pierre Auger Observatory: Contributions to the 33rd International Cosmic Ray Conference (ICRC 2013)

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    Ultrahigh Energy Neutrinos at the Pierre Auger Observatory

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    The Pierre Auger Observatory: Contributions to the 33rd International Cosmic Ray Conference (ICRC 2013)

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    Contributions of the Pierre Auger Collaboration to the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July 201

    Results of a self-triggered prototype system for radio-detection of extensive air showers at the Pierre Auger Observatory

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    The Cosmic Ray Energy Spectrum and Related Measurements with the Pierre Auger Observatory: Presentations for the 31st International Cosmic Ray Conference, Lodz , Poland, July 2009 / Pierre Auger Collaboration ; J. Abraham, P. Abreu, M. Aglietta, C. Aguirre, E.J. Ahn [und 465 weitere]

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