Dark Matter, Baryon Number, and Cosmic-Ray Antinuclei

TL;DR

This paper proposes models where dark matter annihilates into baryon and lepton number-carrying particles, leading to significantly increased fluxes of cosmic-ray antinuclei, potentially explaining AMS observations.

Contribution

It introduces a class of GUT-motivated models that enhance antinuclei fluxes from dark matter annihilation, surpassing conventional predictions.

Findings

Enhanced antideuteron and antihelium fluxes by an order of magnitude or more.

Potential explanation for AMS's observed antinuclei events.

Models consistent with grand unified theories.

Abstract

Antideuterons and antihelium nuclei in the cosmic-ray spectrum have long been considered a smoking gun signature of dark matter annihilation, making the tentative observation of several such events by AMS highly intriguing. Conventional dark matter models, however, can produce only up to O(1) antideuteron events at AMS and are not capable of generating observable fluxes of antihelium. In this letter, we propose a class of models in which dark matter annihilates into particles carrying baryon and lepton number, whose subsequent decays produce enhanced fluxes of antinucleons and antinuclei. Such scenarios are motivated by Grand Unified Theories and can lead to an order-of-magnitude or larger enhancement in the resulting antideuteron and antihelium-3 fluxes, providing a means by which to potentially explain the events reported by the AMS Collaboration.