Composition Sensitivity (for the Cosmic Ray Anisotropy with SWGO)

TL;DR

This paper explores how the future SWGO observatory can analyze cosmic-ray anisotropy evolution across energies and mass groups, enhancing understanding of cosmic-ray origins.

Contribution

It demonstrates the potential of SWGO to discriminate cosmic-ray mass groups and probe dipole evolution with rigidity, advancing cosmic-ray anisotropy studies.

Findings

SWGO can effectively separate cosmic-ray mass groups.

The observatory can probe dipole evolution with energy and rigidity.

Results support SWGO's role in understanding cosmic-ray origins.

Abstract

A number of cosmic-ray observatories have measured a change in both phase and amplitude of the dipole component in the distribution of cosmic-ray arrival directions above a primary energy of 100 TeV. We focus on probing the cosmic-ray dipole and multipole evolution in the energy region of mutli TeV to beyond PeV with a future large-area gamma-ray observatory, such as the Southern Wide-field Gamma-ray Observatory (SWGO). The ability to discriminate between different mass groups is essential to understand the origin of this evolution. Through a consideration of the energy and mass resolution for cosmic-ray detection by such an observatory, we estimate its separation power for decomposing the full-particle anisotropy into mass groups. In particular, we explore the feasibility of probing the dipole evolution with rigidity with SWGO. In this way, we demonstrate the great potential that this instrument offers for providing a deeper understanding of the origin of the cosmic-ray anisotropy.