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arXiv · 1011.2637

Measurement of the antiproton/proton ratio in the few-TeV energy range with ARGO-YBJ

G. Di Sciascio·R. Iuppa
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Abstract

Cosmic ray antiprotons provide an important probe for the study of cosmic ray propagation in the interstellar space and to investigate the existence of Galactic dark matter. The ARGO-YBJ experiment is observing the Moon shadow with high statistical significance at an energy threshold of a few hundred GeV. Using all the data collected until November 2009, we set two upper limits on the antip/p flux ratio: 5% at an energy of 1.4 TeV and 6% at 5 TeV with a confidence level of 90%. In the few-TeV range the ARGO-YBJ results are the lowest available, useful to constrain models for antiproton production in antimatter domains.

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G. Di Sciascio, R. Iuppa. 2010-11-11. Measurement of the antiproton/proton ratio in the few-TeV energy range with ARGO-YBJ. https://doi.org/10.1016/j.nuclphysbps.2011.03.040

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