1,940 research outputs found
LHCf: physics results on forward particle production at LHC
The LHCf experiment is dedicated to the measurement of very forward particle
production in the high energy hadron-hadron collisions at LHC, with the aim of
improving the cosmic-ray air shower developments models. The detector has taken
data in p-p collisions at = 900 GeV, 2.76 TeV and 7 TeV, and in p/Pb
collisions at = 5 TeV. The results of forward production spectra of
photons, neutral pions and neutrons, compared with the models most widely used
in the High Energy Cosmic Ray physics, are presented in this paper.Comment: Presented at EDS Blois 2013 (arXiv:1309.5705
On the Special Significance of the Latest PAMELA Results in Astroparticle Physics
In continuation of their earlier measurements, the PAMELA group reported data
on antiproton flux and ratios in 2010 at much higher energies. In
past we had dealt with these specific aspects of PAMELA data in great detail
and each time we captured the contemporary data-trends quite successfully with
the help of a multiple production model of secondary antiprotons with some
non-standard ilk and with some other absolutely standard assumptions and
approximations. In this work we aim at presenting a comprehensive and valid
description of all the available data on antiproton flux and the nature of
ratios at the highest energies reported so far by the PAMELA
experiment in 2010. The main physical implication of all this would, in the
end, be highlighted.Comment: 8 pages, 6 figure
Dark Matter Annihilation and the PAMELA, FERMI and ATIC Anomalies
If dark matter (DM) annihilation accounts for the tantalizing excess of
cosmic ray electron/positrons, as reported by the PAMELA, ATIC, HESS and FERMI
observatories, then the implied annihilation cross section must be relatively
large. This results, in the context of standard cosmological models, in very
small relic DM abundances that are incompatible with astrophysical
observations. We explore possible resolutions to this apparent conflict in
terms of non-standard cosmological scenarios; plausibly allowing for large
cross sections, while maintaining relic abundances in accord with current
observations.Comment: 13 pages, 3 figures; published for publication in Physical Review
Cosmic Ray Physics with ACORDE at LHC
The use of large underground high-energy physics experiments, for comic ray
studies, have been used, in the past, at CERN, in order to measure, precisely,
the inclusive cosmic ray flux in the energy range from 2x10^10 - 2x10^12 eV.
ACORDE, ALICE Cosmic Rays DEtector, will act as Level 0 cosmic ray trigger and,
together with other ALICE apparatus, will provide precise information on cosmic
rays with primary energies around 10^15 - 10^17 eV. This paper reviews the main
detector features, the present status, commissioning and integration with other
apparatus. Finally, we discuss the ACORDE-ALICE cosmic ray physics program.Comment: Contribution to the 2007 Europhysics Conference on High Energy
Physics - Manchester, England 19-25 July 2007; 3 pages, 3 figure
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