Related papers: The elusive synchrotron precursor of collisionless…
Many relativistic plasma environments in high-energy astrophysics, including pulsar wind nebulae, hot accretion flows onto black holes, relativistic jets in active galactic nuclei and gamma-ray bursts, and giant radio lobes, are naturally…
The efficiency of particle acceleration at shock waves in relativistic, magnetized astrophysical outflows is a debated topic with far-reaching implications. Here, for the first time, we study the impact of turbulence in the pre-shock…
We model relativistically colliding plasma by PIC simulations in one and two spatial dimensions, taking an ion-to-electron mass ratio of 400. Energy dissipation by a wave precursor of mixed polarity and different densities of the colliding…
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities) created in collisionless shocks are responsible for particle…
It is generally believed that the radiation of relativistic particles in a curved magnetic field proceeds in either the synchrotron or the curvature radiation modes. In this paper we show that in strong curved magnetic fields a significant…
Laser-ablated high-energy-density (HED) plasmas offer a promising route to study astrophysically relevant processes underlying collisionless shock formation, magnetic field amplification, and particle acceleration in the laboratory. Using…
The physics of instabilities in the precursor of relativistic collisionless shocks is of broad importance in high energy astrophysics, because these instabilities build up the shock, control the particle acceleration process and generate…
We use the Chandra X-ray Observatory to study the region in the Tycho supernova remnant between the blast wave and the shocked ejecta interface or contact discontinuity. This zone contains all the history of the shock-heated gas and…
A particle acceleration mechanism by radiation pressure of precursor waves in a relativistic shock is studied. For a relativistic, perpendicular shock with the upstream bulk Lorentz factor of $\gamma_1 \gg 1$, large amplitude…
We model rapid variability of multifrequency emission from blazars occurring across the electromagnetic spectrum (from radio to gamma-rays). Lower energy emission is produced by the synchrotron mechanism, whereas higher energy emission is…
An equation is derived to calculate the dynamics of relativistic magnetized plasma which decelerates by sweeping up matter from the ISM. Reduction to the non-radiative and radiative regimes is demonstrated. The evolving electron momentum…
The theory of Non-Linear Diffusive Shock Acceleration (NLDSA) predicts the formation of a precursor upstream of the shock, where accelerated particles diffuse and induce magnetic field amplification through streaming instability. The non…
Dense quantum plasmas are ubiquitous in planetary interiors and in compact astrophysical objects, in semiconductors and micro-mechanical systems, as well as in the next generation intense laser-solid density plasma interaction experiments…
Radiative shocks, behind which gas cools faster than the dynamical time, play a key role in many astrophysical transients, including classical novae and young supernovae interacting with circumstellar material. The dense layer behind high…
We herein investigate shock formation and particle acceleration processes for both protons and electrons in a quasi-parallel high-Mach-number collisionless shock through a long-term, large-scale particle-in-cell simulation. We show that…
Particle acceleration in collisionless plasma systems is a central question in astroplasma and astroparticle physics. The structure of the acceleration regions, electron-ion energy equilibration, preacceleration of particles at shocks to…
Radio relics are diffuse radio sources in galaxy clusters that are associated with merger shock waves. Detailed observations of radio relics in total intensity and in polarisation show complex structures on kiloparsec scales. The relation…
Hot-cold ablative mixing plasmas are ubiquitous in astrophysical and laboratory systems, where a cold/dense plasma is roughly in pressure balance with a hot/dilute plasma. Examples include the plasma thermal quench during major disruptions…
A full particle simulation study is carried out for studying microinstabilities generated at the shock front of perpendicular collisionless shocks. The structure and dynamics of shock waves are determined by Alfven Mach number and plasma…
While collisionless plasmas are ubiquitously present near astrophysical compact objects, the impact that their composition has on the high-energy emission is presently unknown. We present the first investigation of particle-acceleration…