| Texto completo | |
| Autor(es): |
Barreto-Mota, Lucas
;
de Gouveia Dal Pino, Elisabete M.
;
Xu, Siyao
;
Lazarian, Alexandre
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ASTROPHYSICAL JOURNAL; v. 988, n. 2, p. 17-pg., 2025-08-01. |
| Resumo | |
Cosmic rays (CRs) interact with turbulent magnetic fields in the interstellar medium (ISM), generating nonthermal emission. After many decades of studies, the theoretical understanding of their diffusion in the ISM continues to pose a challenge. This study numerically explores a recent prediction termed "mirror diffusion" and its synergy with the traditional diffusion mechanism based on gyroresonant scattering. Our study combines 3D MHD simulations of star-forming regions with test particle simulations to analyze CR diffusion. We demonstrate the significance of mirror diffusion in CR diffusion parallel to the magnetic field when the mirroring condition is satisfied. Our results support the theoretical expectation that the resulting particle propagation arising from mirror diffusion in combination with much faster diffusion induced by gyroresonant scattering resembles a Levy-flight-like propagation. Our study highlights the necessity to reevaluate the diffusion coefficients traditionally adopted in the ISM based on gyroresonant scattering alone. For instance, our simulations imply a diffusion coefficient similar to 10(27) cm(2) s(-1) for particles with a few hundred TeV within regions spanning a few parsecs around the source. This estimate is in agreement with gamma-ray observations, which show the relevance of our results for the understanding of gamma-ray emission in star-forming regions. (AU) | |
| Processo FAPESP: | 21/02120-0 - Investigação de fenômenos de astrofísica de plasmas e altas energias, instalação do ASTRI-Mini Array & construção dos telescópios de tamanho pequeno do Cherenkov Telescope Array (CTA-SSTs) |
| Beneficiário: | Elisabete Maria de Gouveia Dal Pino |
| Modalidade de apoio: | Auxílio à Pesquisa - Projetos Especiais |
| Processo FAPESP: | 13/10559-5 - Investigação de fenômenos de altas energias e plasmas astrofísicos: teoria, simulações numéricas, observações e desenvolvimento de instrumentação para o Cherenkov Telescope Array (CTA) |
| Beneficiário: | Elisabete Maria de Gouveia Dal Pino |
| Modalidade de apoio: | Auxílio à Pesquisa - Projetos Especiais |