Nuclear interactions of low-energy cosmic rays with the interstellar medium

TL;DR

This paper reviews the significance of low-energy cosmic rays in interstellar chemistry and nucleosynthesis, highlighting the challenges in direct detection and exploring gamma-ray line emission as an indirect detection method.

Contribution

It provides a comprehensive overview of low-energy cosmic ray interactions with the interstellar medium and discusses potential gamma-ray detection techniques.

Findings

Light element abundances inform cosmic-ray studies

Gamma-ray line emission offers a detection pathway

Low-energy cosmic rays influence interstellar chemistry

Abstract

Cosmic rays of kinetic energies below ~1 GeV per nucleon are thought to play a key role in the chemistry and dynamics of the interstellar medium. They are also thought to be responsible for nucleosynthesis of the light elements Li, Be, and B. However, very little is known about the flux and composition of low-energy cosmic rays since the solar modulation effect makes impossible a direct detection of these particles near Earth. We first discuss the information that the light elements have brought to cosmic-ray studies. We then discuss the prospects for detection of nuclear gamma-ray line emission produced by interaction of low-energy cosmic rays with interstellar nuclei.