Anomalous diffusion of cosmic rays: A geometric approach

• Main Authors: Salvatore Buonocore, Mihir Sen
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2021-05-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/5.0049401

In this work, we analyze the process leading to the occurrence of anomalous transport phenomena associated with galactic cosmic rays propagating through the interstellar space. The origin of non-conventional transport is found in the dynamics of cosmic rays dominated by long uninterrupted flights interspersed with interactions with magnetized scattering clouds. The process is analyzed via a geometric Monte Carlo model that is able to mimic the intrinsic non-local character of the investigated transport phenomena. Numerical results show the existence of ranges of density and re-emission strengths of the interstellar magnetic clouds leading to heavy-tailed (Lévy α-stable) distributions of the propagating cosmic rays denoting a marked superdiffusive character. The correspondence between the geometric Monte Carlo integration method proposed in this work and the fractional Green’s functions suggests a novel approach to efficiently performing integration in higher dimensional spaces.