Dark Matter after BESS-Polar II

TL;DR

This paper uses precise measurements of antiproton flux from BESS-Polar II to set new constraints on dark matter annihilation, excluding certain WIMP models in the 3-20 GeV mass range.

Contribution

It provides the first constraints on dark matter annihilation from BESS-Polar II data, improving limits on the annihilation cross section for masses up to 200 GeV.

Findings

No excess antiprotons detected beyond secondary production.

Strong limits set on dark matter annihilation cross sections.

Excluded thermal WIMPs with 3-20 GeV mass if they predominantly annihilate into quarks.

Abstract

The BESS-Polar collaboration has recently performed a precise measurement of the local antiproton flux which is consistent with a pure secondary production of antiprotons. We constrain a possible primary component originating from dark matter pair-annihilations. We derive limits on the annihilation cross section which are stronger than or comparable to those from the PAMELA satellite experiment for dark matter masses up to 200 GeV. Especially, we exclude thermal WIMPs with masses in the range 3-20 GeV if they annihilate dominantly into quark pairs unless their cross section is velocity suppressed.