Related papers: Diagnosing Cosmic Ray Modified Shocks with H {\alp…
Since the Lalpha rocket observations of (Gabriel, Solar Phys. 21, 392, 1971), it has been realized that the hydrogen (H) lines could be observed in the corona and offer an interesting diagnostic for the temperature, density, and radial…
A numerical scheme that incorporates a thermal leakage injection model into a combined gas dynamics and cosmic ray (CR, hereafter) diffusion-convection code has been developed. The particle injection is followed numerically by filtering the…
The torsion modified Maxwell-Proca equations when applied to describe a plasma is shown to lead to a correction to the Debye screening length.For hot new born neutron stars the torsion correction is shown to be significant.This effect may…
Diffusive shock acceleration is considered as the main mechanism for particle energization in supernova remnants, as well as in other classes of sources. The existence of some remnants that show a bilateral morphology in the X-rays and…
The theory of diffusive particle acceleration explains the spectral properties of the cosmic rays below energies of approx. 10^6 GeV as produced at strong shocks in supernova remnants (SNR's). To supply the observed flux of cosmic rays, a…
The structure of relativistic radiation mediated shocks (RRMS) propagating into a cold electron-proton plasma is calculated and analyzed. A qualitative discussion of the physics of relativistic and non relativistic shocks, including order…
Strong shocks propagating into a partially ionized medium are often associated with optical Balmer lines. This emission is due to impact excitation of neutral hydrogen by hot protons and electrons in the shocked gas. The structure of such…
Diffusive shock acceleration at collisionless shocks is thought to be the source of many of the energetic particles observed in space. Large-scale spatial variations of the magnetic field has been shown to be important in understanding…
We demonstrate that cosmic rays form filamentary structures in the precursors of supernova remnant shocks due to their self-generated magnetic fields. The cosmic-ray filamentation results in the growth of a long wavelength instability, and…
Before cosmic reionization, hydrogen atoms acquire a spin polarization quadrupole through interaction with the anisotropic 21-cm radiation field. The interaction of this quadrupole with anisotropies in the cosmic microwave background (CMB)…
When galaxy clusters collide, they generate shock fronts in the hot intracluster medium. Observations of these shocks can provide valuable information on the merger dynamics and physical conditions in the cluster plasma, and even help…
We show that a purely kinetic approach to the excitation of waves by cosmic rays in the vicinity of a shock front leads to predict the appearance of a non-alfv\'enic fastly growing mode which has the same dispersion relation as that…
The analytical theory of diffusive cosmic ray acceleration at parallel stationary shock waves with magnetostatic turbulence is generalized to arbitrary shock speeds $V_s=\beta_1c$, including in particular relativistic speeds. This is…
Cosmic rays are the most energetic particles arriving at earth. Although most of them are thought to be accelerated by supernova remnants, the details of the acceleration process and its efficiency are not well determined. Here we show that…
We study the ensemble of linear polarization measurement in the optical afterglows of long-duration gamma-ray bursts. We assume a non sideways-expanding top-hat jet geometry and use the relatively large number of measurements under the…
We investigate the production of circularly polarised X and gamma-ray signals in cosmic accelerators such as supernova remnants and AGN jets. Proton-proton and proton-photon collisions within these sites produce a charge asymmetry in the…
We calculate the polarization of synchrotron radiation produced at the relativistic reconfinement shocks, taking into account globally ordered magnetic field components, in particular toroidal and helical fields. In these shocks, toroidal…
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…
Cosmic-ray production in young supernova remnant (SNR) shocks is expected to be efficient and strongly nonlinear. In nonlinear, diffusive shock acceleration, compression ratios will be higher and the shocked temperature lower than…
Many fast supernova remnant shocks show spectra dominated by Balmer lines. The H$\alpha$ profiles have a narrow component explained by direct excitations and a thermally Doppler broadened component due to atoms that undergo charge exchange…