Related papers: On the Cosmic Ray Driven Firehose Instability
In the Universe matter outside of stars and compact objects is mostly composed of collisionless plasma. The interaction of a supersonic plasma flow with an obstacle results in collisionless shocks that are often associated with intense…
Supernova explosions into predecessor stellar winds can lead to particle acceleration, which we suggest can explain most of the observed cosmic rays of the nuclei of Helium and heavier elements, from GeV in particle energies up to near $3…
We investigate the observability, by direct and indirect means, of a shock precursor arising from magnetic field amplification by cosmic rays. We estimate the depth of such a precursor under conditions of nonresonant amplification, which…
Fast reconnection operating in magnetically dominated plasmas is often invoked in models for magnetar giant flares, for magnetic dissipation in pulsar winds, or to explain the gamma-ray flares observed in the Crab nebula, hence its…
Cosmic-ray acceleration at non-relativistic shocks relies on scattering by turbulence that the cosmic rays drive upstream of the shock. We explore the rate of energy transfer from cosmic rays to non-resonant Bell modes and the spectral…
We show that an alpha effect is driven by the cosmic ray Bell instability exciting left-right asymmetric turbulence. Alfven waves of a preferred polarization have maximally helical motion, because the transverse motion of each mode is…
The relationship between a decaying plasma turbulence and proton fire hose instabilities in a slowly expanding plasma is investigated using three-dimensional (3-D) hybrid expanding box simulations. We impose an initial ambient magnetic…
We show that the Bell instability, which is widely considered potentially important for cosmic-ray acceleration, is the low-frequency limit of a gyroresonant interaction between the protons of the interstellar medium and shear-Alfv\'en…
We investigate the physics of particle acceleration at non-relativistic shocks exploiting two different and complementary approaches, namely a semi-analytic modeling of cosmic-ray modified shocks and large hybrid (kinetic protons/fluid…
Supernovae of Type Ia are used as standard candles for cosmological observations despite the as yet incomplete understanding of their explosion mechanism. In one model, these events are thought to result from subsonic burning in the core of…
A brief analysis of the proton parallel and oblique firehose instability is presented from a fluid perspective and the results are compared to kinetic theory solutions obtained by the WHAMP code. It is shown that the classical CGL model…
Galactic cosmic rays are believed to be mostly accelerated at supernova shocks. However, the interstellar magnetic field is too weak to efficiently accelerate galactic cosmic rays up to the highest energies, i.e. $10^{15}$ eV. A stronger…
In the leptonic scenario for TeV emission from a few well-observed shell-type TeV supernova remnants (STTSNRs), very weak magnetic fields are inferred. If fast-mode waves are produced efficiently in the shock downstream, we show that they…
We study the effects of heat flows and velocity shear on the parallel firehose instability in weakly collisional plasma flow. For this purpose we apply an anisotropic 16-moments MHD fluid closure model that takes into account the pressure…
In the solar wind electron velocity distributions reveal two counter-moving populations which may induce electromagnetic (EM) beaming instabilities known as heat flux instabilities. Depending on plasma parameters two distinct branches of…
Studies of energetic particle acceleration at collisionless shocks by the diffusive shock acceleration process indicate that completely smooth cosmic ray dominated shock structures are possible. The existence of these is discussed and…
We investigate effects of cosmic-rays on the linear growth of the Kelvin-Helmholtz instability. Cosmic-rays are treated as an adiabatic gas and allowed to diffuse along magnetic field lines. We calculated the dispersion relation of the…
The processes responsible for the broad-band radiation of the young supernova remnant Cas A are explored using a new code which is designed for a detailed treatment of the diffusive shock acceleration of particles in nonlinear regime. The…
The present paper reviews recent advances in the theory of nonlinear driven magnetohydrodynamic (MHD) waves in slow and Alfven resonant layers. Simple estimations show that in the vicinity of resonant positions the amplitude of variables…
We present in this paper both a linear study and numerical relativistic MHD simulations of the non-resonant streaming instability occurring in the precursor of relativistic shocks. In the shock front restframe, we perform a linear analysis…