Related papers: X-ray Synchrotron Polarization from Turbulent Plas…
The present article investigates magnetic amplification in the upstream medium of SNR blast wave through both resonant and non-resonant regimes of the streaming instability. It aims at a better understanding of the diffusive shock…
A review of the main issues in the field of particle acceleration in Supernova Remnants is provided in the context of future X-ray observations with Simbol-X. After a summary of the nonthermal acceleration mechanisms at work, I briefly…
Linearly polarized Balmer line emissions from supernova remnant shocks are studied taking into account the energy loss of the shock owing to the production of nonthermal particles. The polarization degree depends on the downstream…
The collision of two plasma clouds at a speed that exceeds the ion acoustic speed can result in the formation of shocks. This phenomenon is observed not only in astrophysical scenarios such as the propagation of supernova remnant (SNR)…
Context: Multiwavelength observations of supernova remnants can be explained within the framework of the diffusive shock acceleration theory, which allows effective conversion of the explosion energy into cosmic rays. Although the models of…
A nonresonant cosmic-ray-current-driven instability may operate in the shock precursors of young supernova remnants and be responsible for magnetic-field amplification, plasma heating and turbulence. Earlier simulations demonstrated…
Particle acceleration mechanisms in supermassive black hole jets, such as shock acceleration, magnetic reconnection, and turbulence, are expected to have observable signatures in the multi-wavelength polarization properties of blazars. The…
We investigate the turbulent structures in the Tycho supernova remnant (SNR) by applying two-point autocorrelation and power spectral analyses to high-resolution X-ray and radio images. Using cleaned Chandra and VLA data, we derive…
Young supernova remnants (SNRs) shocks are believed to be the main sites of galactic cosmic rays production, showing X-ray synchrotron dominated spectra in the vicinity of their shock. While a faint thermal signature left by the shocked…
We develop a model of particle energization and emission from strongly turbulent black-hole coronae. Our local model is based on a set of 2D radiative particle-in-cell simulations with an electron-ion plasma composition, injection and…
We report results from deep observations (~750 ks) of Tycho's supernova remnant (SNR) with NuSTAR. Using these data, we produce narrow-band images over several energy bands to identify the regions producing the hardest X-rays and to search…
Supernova remnants (SNR) are now widely believed to be a source of cosmic rays (CRs) up to an energy of 1 PeV. The magnetic fields required to accelerate CRs to sufficiently high energies need to be much higher than can result from…
If highly efficient, cosmic ray production can have a significant effect on the X-ray emission from SNRs as well as their dynamical evolution. Using hydrodynamical simulations including diffusive shock acceleration, we produce spectra for…
The shocks of several young supernova remnants (SNR) are often associated with very thin optical filaments dominated by Balmer emission resulting from charge-exchange and collisional excitation between neutral Hydrogen from the interstellar…
Observations of synchrotron radiation across a wide range of wavelengths provide clear evidence that electrons are accelerated to relativistic energies in supernova remnants (SNRs). However, a viable mechanism for the pre-acceleration of…
A number of nearby Northern Hemisphere shell-type Supernova Remnants (SNRs) has been observed in TeV gamma rays, but none of them could be detected so far. This failure calls for a critical reevaluation of the theoretical arguments for…
The author is developing a numerical code with thousands of emission zones to simulate the time-dependent multi-waveband emission from blazars. The code is based on a model in which turbulent plasma flowing at a relativistic speed down a…
Supernova remnants (SNRs) have been regarded as major acceleration sites of Galactic cosmic rays. Recent X-ray studies revealed neutral Fe K$\alpha$ line emission from dense gas in the vicinity of some SNRs, which can be best interpreted as…
Supernova remnants (SNRs) are thought to be one of the major acceleration sites of galactic cosmic rays (CRs) and an important class of objects for high-energy astrophysics. SNRs produce multi-wavelength, non-thermal emission via…
Supernova remnants (SNRs) are often considered as the main sites of acceleration of cosmic rays in our Galaxy, possibly up to the knee. However, their ability to accelerate particles to reach PeV energies is questionable and lacks…