A systematic study on the cosmic ray antiproton flux

TL;DR

This paper systematically analyzes the secondary antiproton flux from cosmic ray interactions, considering uncertainties from propagation and interaction models, and derives constraints on dark matter annihilation from AMS-02 data.

Contribution

It provides a comprehensive evaluation of the uncertainties in antiproton flux predictions and constrains dark matter properties using recent high-precision measurements.

Findings

Different hadronic models yield non-converging antiproton flux predictions.

The EPOS LHC model fits collider data well but predicts a lower antiproton/proton ratio at high energies.

Constraints on dark matter annihilation cross section are derived from AMS-02 data.

Abstract

Recently the AMS-02 collaboration has published the measurement of the cosmic antiproton to proton ratio $\bar{p}/p$ and the $\bar{p}$ flux with a high precision up to $\sim 450\,\mathrm{GeV}$. In this work, we perform a systematic analysis of the secondary antiproton flux generated by the cosmic ray interaction with the interstellar gas. The uncertainty of the prediction originates from the cosmic ray propagation process and the hadronic interaction models. Although the cosmic ray propagation parameters have been well controlled by the AMS-02 $B/C$ ratio data for a specified model, different propagation models can not be discriminated by the $B/C$ data. The $\bar{p}$ flux is also calculated for several hadronic interaction models, which are generally adopted by the cosmic ray community. However, the results for different hadronic models do not converge. We find the EPOS LHC model, which seems to fit the collider data very well, predicts a slightly lower $\bar{p}/p$ ratio than the AMS-02 data at the high energy end. Finally we derive the constraints on the dark matter annihilation cross section from the AMS-02 $\bar{p}/p$ ratio for different propagation and hadronic interaction models.