Colliding-Wind Binaries as a Source of TeV Cosmic Rays

Autor(es)

Kowal, Grzegorz ^[1] ; Falceta-Goncalves, Diego A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Escola Artes Ciencias & Humanidades, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: FRONTIERS IN ASTRONOMY AND SPACE SCIENCES; v. 8, MAY 28 2021.
• Citações Web of Science: 0

Resumo

In addition to gamma-ray binaries which contain a compact object, high-energy and very high-energy gamma rays have also been detected from colliding-wind binaries. The collision of the winds produces two strong shock fronts, one for each wind, both surrounding a shock region of compressed and heated plasma, where particles are accelerated to very high energies. Magnetic field is also amplified in the shocked region on which the acceleration of particles greatly depends. In this work, we performed full three-dimensional magnetohydrodynamic simulations of colliding winds coupled to a code that evolves the kinematics of passive charged test particles subject to the plasma fluctuations. After the run of a large ensemble of test particles with initial thermal distributions, we show that such shocks produce a nonthermal population (nearly 1 % of total particles) of few tens of GeVs up to few TeVs, depending on the initial magnetization level of the stellar winds. We were able to determine the loci of fastest acceleration, in the range of MeV/s to GeV/s, to be related to the turbulent plasma with amplified magnetic field of the shock. These results show that colliding-wind binaries are indeed able to produce a significant population of high-energy particles, in relatively short timescales, compared to the dynamical and diffusion timescales. (AU)

• 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
• Processo FAPESP: 19/03301-8 - Observação e modelagem de regiões ativas solares e estelares em ondas rádio mm/sub-mm
• Beneficiário: Caius Lucius Selhorst
• Modalidade de apoio: Auxílio à Pesquisa - Regular