A Precision Search for WIMPs with Charged Cosmic Rays

TL;DR

This paper uses high-precision cosmic ray data from AMS-02 to improve background modeling and set new limits on WIMP dark matter annihilation, excluding certain mass ranges and confirming a mild excess.

Contribution

It systematically quantifies and reduces uncertainties in antiproton background modeling, fully incorporates cross section uncertainties, and constrains WIMP masses up to 570 GeV.

Findings

Excluded thermal WIMPs up to 570 GeV for annihilation into bottom quarks.

Confirmed a mild excess around 80 GeV with low statistical significance.

Improved background modeling enhances dark matter detection sensitivity.

Abstract

AMS-02 has reached the sensitivity to probe canonical thermal WIMPs by their annihilation into antiprotons. Due to the high precision of the data, uncertainties in the astrophysical background have become the most limiting factor for indirect dark matter detection. In this work we systematically quantify and -- where possible -- reduce uncertainties in the antiproton background. We constrain the propagation of charged cosmic rays through the combination of antiproton, B/C and positron data. Cross section uncertainties are determined from a wide collection of accelerator data and are -- for the first time ever -- fully taken into account. This allows us to robustly constrain even subdominant dark matter signals through their spectral properties. For a standard NFW dark matter profile we are able to exclude thermal WIMPs with masses up to 570 GeV which annihilate into bottom quarks. While we confirm a reported excess compatible with dark matter of mass around 80 GeV, its local (global) significance only reaches 2.2 sigma (1.1 sigma) in our analysis.