Related papers: Diffusive shock acceleration in extragalactic jets
We present the results of simulations of the development of the Kelvin-Helmholtz (KH) instability in a cooled, slab symmetric system. The parameters were chosen to approximate the physical conditions typically found in jets from young…
We use analytic estimates and numerical simulations of test particles interacting with magnetohydrodynamic (MHD) turbulence to show that subsonic MHD turbulence produces efficient second-order Fermi acceleration of relativistic particles.…
We have developed an economical, effective numerical scheme for cosmic-ray transport suitable for treatment of electrons up to a few hundreds of GeV in multidimensional simulations of radio galaxies. The method follows the electron…
Recently, microquasar jets have aroused the interest of many researchers focusing on the astrophysical plasma outflows and various jet ejections. In this work, we concentrate on the investigation of electromagnetic radiation and particle…
We present results from a fully relativistic Monte Carlo simulation of diffusive shock acceleration (DSA) in unmodified shocks. The computer code uses a single algorithmic sequence to smoothly span the range from nonrelativistic speeds to…
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…
The growth rate of long wavelength kinetic instabilities arising due to the interaction of a collimated beam of relativistic particles and a cold unmagnetized plasma are calculated in the ultra relativistic limit. For sufficiently…
We study the evolution of the energy spectrum of cosmic-ray electrons accelerated at spherically expanding shocks with low Mach numbers and the ensuing spectral signatures imprinted in radio synchrotron emission. Time-dependent simulations…
Observations of relativistic jets from black holes systems suggest that particle acceleration often occurs at fixed locations within the flow. These sites could be associated with critical points that allow the formation of standing shock…
We present the results of state-of-the-art simulations of recollimation shocks induced by the interaction of a relativistic jet with an external medium, including the effect of radiative losses of the shocked gas. Our simulations confirm…
Shear flows, ubiquitous in space and astrophysical plasmas, can accelerate particles through turbulence excited by the Kelvin-Helmholtz instability. We present the first numerical study of particle acceleration in non-relativistic,…
We discuss processes accelerating cosmic ray electrons at boundaries of relativistic jets. The resulting spectrum is expected to posses two characteristic components: a power-law distribution at lower energies and a harder high energy…
We numerically solve semiclassical kinetic equations and compute the growth rate of the Dyakonov-Shur instability of a two-dimensional Fermi liquid in a finite length cavity. When electron-electron scattering is fast, we observe the…
The evolutionarity conditions for the MHD shock waves are considered within the framework of the 8-moment approximation for collisionless plasma with heat fluxes. In the general case, evolutionarity diagrams are obtained depending on the…
We present the theoretical background and detailed equations for the synchrotron emission of a shock wave propagating in a relativistic jet. We then show how the evolution of an outburst in this shock-in-jet scenario can be analytically…
We extend the eigenfunction method of computing the power-law spectrum of particles accelerated at a relativistic shock fronts to apply to shocks of arbitrarily high Lorentz factor. In agreement with the findings of Monte-Carlo simulations,…
Diffusive acceleration at collisionless shock waves remains one of the most promising acceleration mechanisms for the description of the origin of cosmic rays at all energies. A crucial ingredient to be taken into account is the reaction of…
We explore electron pre-acceleration at high Mach-number nonrelativistic perpendicular shocks at, e.g., young supernova remnants, which are a prerequisite of further acceleration to very high energies via diffusive shock acceleration. Using…
We investigate the role of the form of the spatial diffusion coefficient in shock acceleration of fast particles. Referring to non-classical diffusion and using the results of numerical (hybrid) simulations tailored for the downstream shock…
High-resolution Very-Long-Baseline Interferometry observations of NGC 1052 show a two sided jet with several regions of enhanced emission and a clear emission gap between the two jets.This gap shrinks with increasing frequency and vanishes…