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Related papers: Non-Maxwellian Proton Velocity Distributions in No…

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If a sizeable fraction of the energy of supernova remnant shocks is channeled into energetic particles (commonly identified with Galactic cosmic rays), then the morphological evolution of the remnants must be distinctly modified. Evidence…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Gilles Ferrand , Anne Decourchelle , Jean Ballet , Romain Teyssier , Federico Fraschetti

We have investigated the effects of a non-thermal electron population on the ionization and recombination rates. The considered electron distribution is defined as a Maxwellian function below a break energy E_b and as a power-law function…

Astrophysics · Physics 2009-11-06 D. Porquet , M. Arnaud , A. Decourchelle

We present a model for the creation of non-thermal particles via diffusive shock acceleration in a colliding-wind binary. Our model accounts for the oblique nature of the global shocks bounding the wind-wind collision region and the finite…

High Energy Astrophysical Phenomena · Physics 2021-04-28 J. M. Pittard , G. E. Romero , G. S. Vila

H-alpha emission from supernova remnants (SNRs) implies the existence of neutral hydrogens in the ambient medium. In the precursor of an SNR shock modified by cosmic rays (CRs), upstream plasmas are pushed by the CR pressure, but neutral…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Yutaka Ohira , Fumio Takahara

Observations show that plasma particles in the solar wind frequently display power-law velocity distributions, which can be isotropic or anisotropic. Particularly, the velocity distribution functions of solar wind electrons are frequently…

Plasma Physics · Physics 2017-11-30 S. F. Tigik , L. T. Petruzzellis , L. F. Ziebell , P. H. Yoon , R. Gaelzer

In this paper we investigate the feasibility of bremsstrahlung radiation from `nonthermal' electrons as a source of hard X-rays from the intracluster medium of clusters of galaxies. With an exact treatment of the Coulomb collisions in a…

Astrophysics · Physics 2013-03-08 Vahé Petrosian , William E. East

We investigate the effect of bulk velocity of the solar wind on the propagation characteristics of ion-cyclotron waves (ICWs). Our model is based on the kinetic theory. We solve the Vlasov equation for O VI ions and obtain the dispersion…

Solar and Stellar Astrophysics · Physics 2015-06-12 S. Dogan , E. R. Pekunlu

We investigate the interaction of nonthermal ions (protons and nuclei) accelerated in an ultrarelativistic blastwave with the pre-existing magnetic field of the medium into which the blastwave propagates. While particle acceleration…

Astrophysics · Physics 2009-11-13 Sean M. Couch , Milos Milosavljevic , Ehud Nakar

We review the presence and signatures of the non-equilibrium processes, both non-Maxwellian distributions and non-equilibrium ionization, in the solar transition region, corona, solar wind, and flares. Basic properties of the non-Maxwellian…

A simplified model of particle transport at a quasiparallel one-dimensional collisionless shock is suggested. In this model the MHD-turbulence behind the shock is dominated by a circularly polarized, large amplitude Alfv\'en wave originated…

Astrophysics · Physics 2008-11-26 M. A. Malkov

Shocks, turbulence and winds all influence the electron velocity distribution in hot plasmas, exciting lower-energy electrons and generating a high-energy (typically power-law) tail. This effect, typically described as a kappa distribution…

Solar and Stellar Astrophysics · Physics 2020-01-08 Xiaohong Cui , Adam R. Foster , Takayuki Yuasa , Randall K. Smith

Measuring shock velocities is crucial for understanding the energy transfer processes at the shock fronts of supernova remnants (SNRs), including acceleration of cosmic rays. Here we present shock velocity measurements on the SNR N132D,…

High Energy Astrophysical Phenomena · Physics 2025-04-07 Yoshizumi Okada , Yuken Ohshiro , Shunsuke Suzuki , Hiromasa Suzuki , Paul P. Plucinsky , Ryo Yamazaki , Hiroya Yamaguchi

Supernova remnants (SNRs), the products of stellar explosions, are powerful astrophysical laboratories, which allow us to study the physics of collisionless shocks, thanks to their bright electromagnetic emission. Blast wave shocks…

High Energy Astrophysical Phenomena · Physics 2023-02-15 Marco Miceli

We discuss the generic characteristics of stochastic particle acceleration by a fully developed turbulence spectrum and show that resonant interactions of particles with high speed waves dominate the acceleration process. To produce the…

Astrophysics · Physics 2009-11-13 Siming Liu , Zhong-Hui Fan , Christopher L. Fryer

The propagation of ion acoustic shocks in nonthermal plasmas is investigated, both analytically and numerically. An unmagnetized collisionless electron-ion plasma is considered, featuring a superthermal (non-Maxwellian) electron…

Plasma Physics · Physics 2015-06-03 S. Sultana , G. Sarri , I. Kourakis

A collisionless shock may be strongly modified by the presence of neutral atoms through the processes of charge exchange between ions and neutrals and ionization of the latter. These two processes lead to exchange of energy and momentum…

High Energy Astrophysical Phenomena · Physics 2015-06-04 P. Blasi , G. Morlino , R. Bandiera , E. Amato , D. Caprioli

We study a velocity-space quasilinear diffusion of the solar wind protons driven by oblique Alfven turbulence at proton kinetic scales. Turbulent fluctuations at these scales possess properties of kinetic Alfven waves (KAWs) that are…

Space Physics · Physics 2013-05-22 Yuriy Voitenko , Viviane Pierrard

In this paper, the expression of the relativistic Maxwell-J\"uttner velocity distribution was deduced in a detailed and didactic way. This distribution was compared with the well-known Maxwell-Boltzmann distribution, which does not take…

General Physics · Physics 2022-02-07 Gilberto Jonas Damião , Clóves Gonçalves Rodrigues

We analyze measured proton and electron temperatures in the high-speed solar wind in order to calculate the separate rates of heat deposition for protons and electrons. When comparing with other regions of the heliosphere, the fast solar…

Solar and Stellar Astrophysics · Physics 2015-05-13 Steven R. Cranmer , William H. Matthaeus , Benjamin A. Breech , Justin C. Kasper

We investigate the growth of hydromagnetic waves driven by streaming cosmic rays in the precursor environment of a supernova remnant shock. It is known that transverse waves propagating parallel to the mean magnetic field are unstable to…

Astrophysics · Physics 2009-11-13 B. Reville , J. G. Kirk , P. Duffy , S. O. Sullivan