Related papers: Diffusive shock acceleration with magnetic field a…
Subsonic, compressive turbulence transfers energy to cosmic rays (CRs), a process known as non-resonant reacceleration. It is often invoked to explain observed ratios of primary to secondary CRs at $\sim \rm GeV$ energies, assuming wholly…
It has been long believed that oblique and quasi-perpendicular configurations in supernova remnants (SNRs) were inefficient at injecting ions into diffusive shock acceleration (DSA), and that the highest energy Galactic cosmic rays (CRs)…
Observations of non-thermal emission from several supernova remnants suggest that magnetic fields close to the blastwave are much stronger than would be naively expected from simple shock compression of the field permeating the interstellar…
Recent precise measurements of cosmic ray (CR) spectra show that the energy distribution of protons is softer than those of heavier nuclei, and there are spectral hardenings for all nuclear compositions above $\sim$200 GV. Models proposed…
Ambipolar diffusion (AD) is believed to be a crucial process for redistributing magnetic flux in the dense molecular gas that occurs in regions of star formation. We carry out numerical simulations of this process in regions of low…
Cosmic ray acceleration in SNRs in the presence of the Alfv\'enic drift is considered. It is shown that spectra of accelerated particles may be considerably softer in the presence of amplified magnetic fields.
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…
Radio relics in merging galaxy clusters are widely interpreted as synchrotron emission from relativistic electrons accelerated at large-scale shocks. However, the efficiency of diffusive shock acceleration (DSA) is expected to be reduced in…
We present numerical modelling of particle acceleration at coronal shocks propagating through a streamer-like magnetic field by solving the Parker transport equation with spatial diffusion both along and across the magnetic field. We show…
We present very-high-resolution 1D MHD simulations of the late-stage supernova remnants (SNR). In the post-adiabatic stage the magnetic field has an important and significant dynamical effect on the shock dynamics, the flow structure, and…
We statistically investigate high-frequency whistler waves (with frequencies higher than $\sim 10$ % of the local elect ron cyclotron frequency) at Earth's bow shock using Magnetospheric Multi-Scale (MMS) spacecraft observations. We focus…
We investigate the escape process from a perpendicular shock region of a spherical shock in the interstellar medium (ISM). The diffusive shock acceleration in the perpendicular shock of supernova remnants (SNRs) has been expected to…
The problem of explaining observed soft X-ray fluxes during solar flares, which invokes acceleration of large fraction of electrons, if the acceleration takes places at the solar coronal loop-top, can potentially be solved by postulating…
We have performed extensive two-dimensional magnetohydrodynamic simulations to study the amplification of magnetic fields when a supernova blast wave propagates into a turbulent interstellar plasma. The blast wave is driven by injecting…
Young supernova remnants are thought to be the sites where cosmic ray acceleration occurs by the mechanism of diffusive shock acceleration. The maximum energy gained in this process is conventionally extimated to have a value close to, but…
The magnetic energy of nonlinear Alfven waves in compressible plasmas may be ponderomotively coupled only to ion-acoustic quasi-modes which modulate the wave phase velocity and cause wave-front steepening. In the collisionless plasma with…
Supernovae remnant shock waves could be at the origin of cosmic rays up to energies in excess of the knee ($E\simeq3\cdot 10^{15} $eV) if the magnetic field is efficiently amplified by the streaming of accelerated particles in the shock…
The acceleration of energetic particle transport in high amplitude magnetosonic and Alfvenic turbulence is considered using the method of Monte Carlo particle simulations, involving integration of particle equations of motion. We derive the…
Diffusive shock acceleration in the environs of a remnant's expanding shell is a popular candidate for the origin of SNR gamma-rays. In this paper, results from our study of non-linear effects in shock acceleration theory and their impact…
Magnetized oblique shocks are of interest in various plasmas, including in astrophysical systems, magneto-inertial confinement fusion experiments, and in aerospace applications. Through experiments on the COBRA pulsed power facility…