Related papers: Heating and Acceleration of Intracluster Medium El…
Non-thermal components are key ingredients for understanding clusters of galaxies. In the hierarchical model of structure formation, shocks and large-scale turbulence are unavoidable in the cluster formation processes. Understanding the…
Clumping and turbulence are expected to affect the matter accreted onto the outskirts of galaxy clusters. To determine their impact on the thermodynamic properties of Abell 2142 we perform an analysis of the X-ray temperature data from…
A primary characteristic of solar flares is the efficient acceleration of electrons to nonthermal deka-keV energies. While hard X-Ray (HXR) observation of bremsstrahlung emission serves as the key diagnostic of these electrons. In this…
The thermal-to-nonthermal partition was found to vary greatly from one flare to another resulting in a broad variety of cases from 'heating without acceleration' to 'acceleration without heating'. Recent analysis of microwave data of these…
The non-thermal acceleration of electrons and ions at an oblique, non-relativistic shock is studied using large scale particle-in-cell (PIC) simulations in one spatial dimension. Physical parameters are selected to highlight the role of…
A critical component of particle acceleration in astrophysical shocks is the non-resonant (Bell) instability, where the streaming of cosmic rays (CRs) leads to the amplification of magnetic fields necessary to scatter particles. In this…
Collisionless plasma shock theory, which applies for example to the afterglow of gamma ray bursts, still contains key issues that are poorly understood. In this paper we study charged particle dynamics in a highly relativistic collisionless…
We investigate the heating of the quasi-free electrons in large rare gas clusters (N exceeding 10^5 atoms) by short laser pulses at moderate intensities (I~10^{15} Wcm^{-2}). We identify elastic large-angle backscattering of electrons at…
Observations with {\em RHESSI} have enabled the detailed study of the structure of dense hard X-ray coronal sources in solar flares. The variation of source extent with electron energy has been discussed in the context of streaming of…
Models for the integrated relativistic electron population in clusters of galaxies are presented. The results depend on the history of electron acceleration in the cluster. If there is no present particle acceleration or other sources, then…
Thermal gas in the center of galaxy clusters can show substantial motions that generate surface-brightness and temperature discontinuities known as cold fronts. The motions may be triggered by minor or off-axis mergers that preserve the…
Strong non-relativistic shocks are known to accelerate particles up to relativistic energies. However, for Diffusive Shock Acceleration electrons must have a highly suprathermal energy, implying a need for very efficient pre-acceleration.…
Some clusters of galaxies have been identified as powerful sources of non-thermal radiation, from the radio to X-ray wavelengths. The classical models proposed for the explanation of this radiation usually require large energy densities in…
Broadband lasers have become a key strategy for mitigating laser plasma instabilities in inertial confinement fusion, yet their impact on collisional inverse bremsstrahlung (IB) heating remains unclear. Using one-dimensional collisional…
Shocks are promising sites of particle acceleration in extragalactic jets. In electron-ion shocks, electrons can be heated up to large Lorentz factors, making them an attractive scenario to explain the high minimum electron Lorentz factors…
Molecular clouds are expected to emit non-thermal radiation due to cosmic ray interactions in the dense magnetized gas. Such emission is amplified if a cloud is located close to an accelerator of cosmic rays and if cosmic rays can leave the…
Non-thermal electron populations are observed throughout the heliosphere. The relaxation of an electron beam is known to produce Langmuir waves which, in turn, may substantially modify the electron distribution function. As the Langmuir…
Recently, strong AGN outbursts at the centers of galaxy clusters have been found. Using a simple model, we study particle acceleration around a shock excited by an outburst and estimate nonthermal emission from the accelerated particles. We…
Most theoretical descriptions of the production of solar flare bremsstrahlung radiation assume the collision of dilute accelerated particles with a cold, dense target plasma, neglecting interactions of the fast particles with each other.…
The collision of two expanding plasma clouds is investigated, emphasizing instabilities and electron energization in the plasma mixing layer. This work is directly relevant to laboratory experiments with explosively-created laser or z-pinch…