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arXiv · 2504.18987

Propagation of UHE cosmic rays in the light of f(R) gravity power-law model

Swaraj Pratim Sarmah
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Abstract

While the origins of ultra-high energy (UHE) cosmic rays (CRs) remain shrouded in uncertainty, several important milestones have been reached in recent years in the experimental study of CRs with energy above 1018 eV. Within the vast expanse of intergalactic space, turbulent magnetic fields (TMFs) are believed to pervade, and these fields could exert a significant influence on the journey of UHECRs across the expanding Universe, which is currently undergoing acceleration. Thus, it is imperative to incorporate these considerations into our theoretical framework to gain a deeper understanding of the empirical observations related to UHECRs. In light of this, our research delves into the impact of UHE particle diffusion in the presence of TMFs, all within the context of the f(R) gravity power-law model. Based on this f(R) model, we explore the diffusive behavior of UHECR protons, particularly focusing on their density enhancement throughout their propagation and their energy spectrum. We found that the f(R) gravity model considered here plays an effective role in the propagation of CRs and the results have lain within our range of interest. Also, we compare our results for flux with observational data like the Pierre Auger Observatory (PAO) and Telescope Array (TA).

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Swaraj Pratim Sarmah. 2025-04-26. Propagation of UHE cosmic rays in the light of f(R) gravity power-law model. https://doi.org/10.1088/1742-6596%2F2957%2F1%2F012002

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