CRPropa 3.3: Toward a Unified Multi-Messenger Framework from GeV to ZeV Energies

TL;DR

CRPropa 3.3 is a comprehensive Monte Carlo framework that enables realistic multi-messenger astrophysics simulations across a broad energy spectrum, incorporating new features like time dependence and advanced nuclear physics.

Contribution

The paper introduces CRPropa 3.3 with significant extensions for multi-messenger studies, including time tracking, dynamic fields, and expanded nuclear cross sections, enhancing simulation realism.

Findings

Supports multi-messenger simulations from GeV to ZeV energies.

Includes new features like time-dependent advection and moving shocks.

Enhances nuclear interaction modeling up to lead (Z=82).

Abstract

We present CRPropa 3.3, the latest release of the publicly available Monte Carlo framework for simulating the propagation of high-energy particles in astrophysical environments. This version introduces significant extensions that enables multi-messenger studies across a broad energy range, from GeV to ZeV. New features include explicit time tracking, time-dependent advection fields, and support for position-dependent radiation backgrounds, for more realistic simulations of Galactic and extragalactic propagation. Nuclear cross sections have been updated and expanded up to lead (Z=82). We illustrate some of these new features, including acceleration at moving shocks and gamma-ray propagation in the interstellar radiation field. Together, these improvements establish CRPropa 3.3 as a comprehensive tool for modelling cosmic rays, gamma rays, and their secondaries in structured, time-dependent environments, setting the stage for next-generation multi-messenger astrophysics.