Atmospheric Antideuteron Flux Within a Dynamical Coalescence Approach

TL;DR

This paper models atmospheric secondary antideuteron flux using a dynamical coalescence approach combined with a multiphase transport model, providing a new theoretical baseline relevant for dark matter detection efforts.

Contribution

It introduces a novel modeling framework for atmospheric antideuteron flux that includes tertiary contributions, improving the understanding of background signals for dark matter searches.

Findings

Atmospheric antideuteron flux is consistent with existing calculations.

Flux remains below current experimental upper limits.

Background dominates below 0.26 GeV/n energy.

Abstract

Cosmic antideuterons are considered as one of the most promising tools for the indirect detection of dark matter due to their ultra-low astrophysical backgrounds. Currently only upper limits on the antideuteron flux exist, but advancements in experimental detection technology may soon lead to positive signals. A major source of background is the production of secondary antideuterons through collisions of cosmic rays with the surrounding medium. In this study, antideuteron production is modeled using a multiphase transport model (AMPT) coupled with a dynamical coalescence model. By applying a widely used leaky box model and incorporating specific processes, we present a new theoretical baseline for atmospheric secondary antideuteron flux, including a tertiary contribution, from primary cosmic rays interacting with Earth's atmosphere. Our results indicate that the atmospheric antideuteron flux are within the range of various existing calculations and remain well below the upper limits set by the Balloon-borne Experiment with a Superconducting Spectrometer (BESS). The atmospheric antideuteron is found to dominate the antideuteron background at kinetic energies below $0.26 $ GeV/n.