Prospects to verify a possible dark matter hint in cosmic antiprotons with antideuterons and antihelium

TL;DR

This paper evaluates the potential of detecting antideuterons and antihelium in cosmic rays to verify a possible dark matter signal suggested by antiproton data, considering experimental capabilities and uncertainties.

Contribution

It provides a detailed analysis of the prospects for observing antinuclei as a complementary test for dark matter, incorporating experimental sensitivities and theoretical uncertainties.

Findings

Antideuteron signals are within detection capabilities of GAPS and AMS-02.

Results set upper limits on dark matter annihilation signals based on current antiproton data.

Potential antihelium fluxes could be consistent with dark matter interpretations.

Abstract

Cosmic rays are an important tool to study dark matter annihilation in our Galaxy. Recently, a possible hint for dark matter annihilation was found in the antiproton spectrum measured by AMS-02, even though the result might be affected by theoretical uncertainties. A complementary way to test its dark matter interpretation would be the observation of low-energy antinuclei in cosmic rays. We determine the chances to observe antideuterons with GAPS and AMS-02, and the implications for the ongoing AMS-02 antihelium searches. We find that the corresponding antideuteron signal is within the GAPS and AMS-02 detection potential. If, more conservatively, the putative signal was considered as an upper limit on DM annihilation, our results would indicate the highest possible fluxes for antideuterons and antihelium compatible with current antiproton data.