相关论文: Colliding-wind binary systems: Diffusive shock acc…
Spider pulsars are binary systems composed of a millisecond pulsar and a low-mass companion. Their X-ray emission, varying with orbital phase, originates from synchrotron radiation produced by high-energy electrons accelerated at the…
The effects of collisional processes in the hot QCD medium to thermal dilepton production from $q\overline{q}$ annihilation in relativistic heavy-ion collisions have been investigated. The non-equilibrium corrections to the momentum…
Galactic cosmic rays (CRs) are accelerated at the forward shocks of supernova remnants (SNRs) via diffusive shock acceleration (DSA), an efficient acceleration mechanism that predicts power-law energy distributions of CRs. However,…
Electron resonant scattering by high-frequency electromagnetic whistler-mode waves has been proposed as a mechanism for solar wind electron scattering and pre-acceleration to energies that enable them to participate in shock drift…
Particle acceleration is an ubiquitous phenomenon in astrophysical and space plasma. Diffusive shock acceleration (DSA) and stochastic turbulent acceleration are known to be the possible mechanisms for producing very high energetic…
We use 1+1/2 dimensional particle-in-cell plasma simulations to study the interaction of a relativistic, strongly magnetized wind with an ambient medium. Such an interaction is a plausible mechanism which leads to generation of cosmological…
WR 140 is a long-period, highly eccentric Wolf-Rayet star binary system with exceptionally well-determined orbital and stellar parameters. Bright, variable X-ray emission is generated in shocks produced by the collision of the winds of the…
After introduction we focus on: the transport of charged particles, the acceleration of ions at shocks, and the acceleration of electrons at shocks. Chapter 2 studies the propagation of solar energetic particles(SEPs) in turbulent magnetic…
We have developed a numerical model for the temporal evolution of particle and photon spectra resulting from nonthermal processes at the shock fronts formed in merging clusters of galaxies. Fermi acceleration is approximated by injecting…
One of the basic properties of the solar wind, that is the high speed of the fast wind, is still not satisfactorily explained. This is mainly due to the theoretical difficulty of treating weakly collisional plasmas. The fluid approach…
We consider nebulae which are created around binary systems containing rotation powered pulsars and companion stars with strong stellar winds. It is proposed that the stellar and pulsar winds have to mix at some distance from the binary…
A new numerical model of the nonlinear diffusive shock acceleration is presented. It is used for modeling of particle acceleration in supernova remnants. The model contains coupled spherically symmetric hydrodynamic equations and the…
We study how a high-speed solar wind stream embedded in a slow solar wind affects the transport and energy changes of solar energetic protons in interplanetary space, assuming different levels of cross-field diffusion. This is done using a…
Diffusive shock acceleration (DSA) is a prominent mechanism for energizing charged particles up to very large rigidities at astrophysical collisionless shocks. In addition to ions and electrons, it has been proposed that interstellar dust…
Pulsar wind nebulae are efficient particle accelerators, and yet the processes at work remain elusive. Self-generated, microturbulence is too weak in relativistic magnetized shocks to accelerate particles over a wide energy range,…
We have analysed the X-ray emission from a sample of close WR+O binaries using data from the public Chandra and XMM-Newton archives. Global spectral fits show that two-temperature plasma is needed to match the X-ray emission from these…
Radio observations are an effective tool to discover particle acceleration regions in colliding-wind binaries, through detection of synchrotron radiation; these regions are natural laboratories for the study of relativistic particles.…
A two-dimensional (2D) shock-rest-frame model for particle simulations is developed. Then full kinetic dynamics of a perpendicular collisionless shock is examined by means of a 2D full particle simulation. We found that in the 2D simulation…
In this paper we review the possible radiation mechanisms for the observed non-thermal emission in clusters of galaxies, with a primary focus on the radio and hard X-ray emission. We show that the difficulty with the non-thermal,…
We make the first observation-based calculation of the energy that goes into cosmic-ray protons versus cosmic ray electrons in shock acceleration during structure formation. We find a ratio of energy in cosmic ray protons to energy in…