Studies of the UHECR propagation in the Galactic Magnetic Field

TL;DR

This paper simulates how ultra-high energy cosmic rays are deflected by the Galactic magnetic field, affecting their observed arrival directions and exposure, with implications for source identification.

Contribution

It provides detailed simulations of UHECR propagation considering different GMF models and primary particles, highlighting their impact on cosmic ray deflections and observational exposure.

Findings

Different GMF assumptions lead to distinct deflection patterns.

The GMF influences the exposure of UHECR experiments to extragalactic sources.

Simulation results can help interpret correlations with nearby AGN.

Abstract

We present the results of simulations of the ultra-high energy cosmic ray (UHECR) propagation in the Galactic magnetic field (GMF). Different assumptions on the large-scale GMF structure and/or primary particle lead to distinctly different deflection patterns of the highest energy cosmic rays (CR). The GMF modifies the exposure of an UHECR experiment to the extragalactic sky. We estimated these effects for the Pierre Auger experiment. Further forward-tracking studies under plausible UHECR sources scenarios will allow for direct comparison with the observed correlation between the nearby active galactic nuclei (AGN) and the highest energy Auger events.