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

TL;DR

This paper reports on measurements of the antiproton to proton flux ratio in the few-TeV energy range using the ARGO-YBJ experiment, providing new upper limits that help constrain cosmic ray and dark matter models.

Contribution

It presents the first upper limits on the antiproton/proton ratio at TeV energies from the ARGO-YBJ experiment, extending the energy range of previous measurements.

Findings

Upper limits of 5% at 1.4 TeV and 6% at 5 TeV on the antiproton/proton flux ratio.

Results are the lowest available in the few-TeV range, constraining models of antimatter domains.

Data supports the absence of significant antimatter regions in cosmic rays at these energies.

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.