Related papers: Cosmic Ray Acceleration at Relativistic Shocks
A new particle acceleration process in a developing Alfv\'{e}n turbulence in the course of successive parametric instabilities of a relativistic pair plasma is investigated by utilyzing one-dimensional electromagnetic full particle code.…
We use 2D and 3D hybrid (kinetic ions - fluid electrons) simulations to investigate particle acceleration and magnetic field amplification at non-relativistic astrophysical shocks. We show that diffusive shock acceleration operates for…
We study interactions of cosmological relics, $X$, of mass $m$ and electric charge $qe$ in the galaxy, including thermalization with the interstellar medium, diffusion through inhomogeneous magnetic fields and Fermi acceleration by…
Relativistic collisionless shocks are associated with efficient particle acceleration when propagating into weakly magnetized homogeneous media; as the magnetization increases, particle acceleration becomes suppressed. We demonstrate that…
Being the most extreme explosions in the universe, gamma-ray bursts (GRBs) provide a unique laboratory to study various plasma physics phenomena. The complex lightcurve and broad-band, non-thermal spectra indicate a very complicated system…
Gamma-Ray Bursts are good candidates of the ``bottom up'' scenario for the generation of the UHE Cosmic Rays. In the most discussed model of GRBs, namely the ``fireball'' model, a highly relativistic shock forms and seems capable of…
In this thesis different numerical methods, as well as applications of the methods to a number of current problems in relativistic astrophysics, are presented. In the first part the theoretical foundation and numerical implementation of a…
Fast particles are accelerated in astrophysical environments by a variety of processes. Acceleration in reconnection sites has attracted the attention of researchers recently. In this letter we analyze the energy distribution evolution of…
We present some recent developments in the theory of particle acceleration at shock fronts in the presence of dynamical reaction of the accelerated particles and self-generation of magnetic field due to streaming instability. The spectra of…
When the pressure of particles accelerated at shock waves is no longer negligible compared to the kinetic pressure of the gas, the linear theory of diffusive shock acceleration breaks down. This is expected in particular when the shock…
The physics of particle acceleration in turbulent plasmas is a topic of broad interest, which is making rapid progress thanks to dedicated, large-scale numerical experiments. The first part of this paper presents an effective theory of…
In this review we confront the current theoretical understanding of particle acceleration at relativistic outflows with recent observational results on various source classes thought to involve such outflows, e.g. gamma-ray bursts, active…
Efficient acceleration of cosmic rays (via the mechanism of diffusive shock acceleration) requires turbulent, amplified magnetic fields in the shock's upstream region. We present results of multidimensional particle-in-cell simulations…
We explore the physics of shock evolution and particle acceleration in non-relativistic collisionless shocks using multidimensional hybrid simulations. We analyze a wide range of physical parameters relevant to the acceleration of cosmic…
An extreme case of electron shock drift acceleration in low Mach number collisionless shocks is investigated as a plausible mechanism of initial acceleration of relativistic electrons in large-scale shocks in galaxy clusters where upstream…
Our numerical simulations show that the reconnection of magnetic field becomes fast in the presence of weak turbulence in the way consistent with the Lazarian and Vishniac (1999) model of fast reconnection. We trace particles within our…
The mechanism of diffusive Fermi acceleration at collisionless plasma shock waves is widely invoked in astrophysics to explain the appearance of non-thermal particle populations in a variety of environments, including sites of cosmic ray…
Kinetic diffusion of cosmic rays ahead of perpendicular shocks induces charge non-neutrality, which is mostly, yet not completely, screened by the bulk plasma via polarization drift current. Hydrodynamic shear instabilities as well as…
Diffusion of cosmic rays (CRs) is the key process of understanding their propagation and acceleration. We employ the description of spatial separation of magnetic field lines in MHD turbulence in Lazarian & Vishniac (1999) to quantify the…
Particle acceleration is expected to take place at shocks that form during the process of large scale structure formation. Electrons accelerated at such shocks can upscatter a small fraction of the photons in the cosmic microwave background…