Probing the astrophysical origin of high-energy cosmic-ray electrons with Monte Carlo simulation

TL;DR

This paper uses a 3D Monte Carlo simulation to investigate the astrophysical sources of high-energy cosmic-ray electrons, focusing on their spectral features and the influence of nearby sources.

Contribution

It introduces a fully three-dimensional, time-dependent Monte Carlo simulation to analyze electron fluctuations and assess the single-source scenario for high-energy cosmic-ray electrons.

Findings

Simulation reveals electron-by-electron fluctuations.

Supports the viability of the single-source hypothesis.

Provides detailed insights into local source contributions.

Abstract

High-energy cosmic-ray electrons reveal some remarkable spectral features, the most noteworthy of which is the rise in the positron fraction above 10~GeV. Due to strong energy loss during propagation, these particles can reach Earth only from nearby sources. Yet, the exact nature of these sources, which most likely manifest themselves in the observed anomalies, remains elusive. The many explanations put forward to resolve this case range from standard astrophysics to exotic physics. In this paper, we discuss the possible astrophysical origin of high-energy cosmic-ray electrons through a fully three-dimensional time-dependent Monte Carlo simulation. This approach, which takes advantage of the intrinsic random nature of cosmic-ray diffusive propagation, provides valuable information on the electron-by-electron fluctuations, making it particularly suitable for analyzing in depth the single-source scenario.