Ciência-IUL
Publicações
Descrição Detalhada da Publicação
Título Revista
Astrophysical Journal Letters
Ano (publicação definitiva)
2009
Língua
Inglês
País
Estados Unidos da América
Mais Informação
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Abstract/Resumo
Ab initio numerical study of collisionless shocks in electron-ion unmagnetized plasmas is performed with fully relativistic particle in cell simulations. The main properties of the shock are shown, focusing on the implications for particle acceleration. Results from previous works with a distinct numerical framework are recovered, including the shock structure and the overall acceleration features. Particle tracking is then used to analyze in detail the particle dynamics and the acceleration process. We observe an energy growth in time that can be reproduced by a Fermi-like mechanism with a reduced number of scatterings, in which the time between collisions increases as the particle gains energy, and the average acceleration efficiency is not ideal. The in depth analysis of the underlying physics is relevant to understanding the generation of high-energy cosmic rays, the impact on the astrophysical shock dynamics, and the consequent emission of radiation.
Agradecimentos/Acknowledgements
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Palavras-chave
Acceleration of particles,Gamma rays: bursts,Methods: numerical
Classificação Fields of Science and Technology
- Ciências Físicas - Ciências Naturais
Registos de financiamentos
Referência de financiamento | Entidade Financiadora |
---|---|
SFRH/BD/35749/2007 | Fundação para a Ciência e a Tecnologia |
PTDC/FIS/66823/2006 | Fundação para a Ciência e a Tecnologia |