Related papers: Particle Acceleration in (by) Accretion Discs

While laser-plasma accelerators have demonstrated a strong potential in the acceleration of electrons up to giga-electronvolt energies, few experimental tools for studying the acceleration physics have been developed. In this paper, we…

First-order Fermi acceleration processes at ultrarelativistic shocks are studied with Monte Carlo simulations. The accelerated particle spectra are derived by integrating the exact particle trajectories in a turbulent magnetic field near…

Binary systems can be powerful sources of non-thermal emission from radio to gamma rays. When the latter are detected, then these objects are known as gamma-ray binaries. In this work, we explore, in the context of gamma-ray binaries,…

Two-dimensional particle simulations of a relativistic Harris current sheet of pair plasmashave demonstrated that the system is unstable to the relativistic drift kink instability (RDKI) and that a new kind of acceleration process takes…

Particle acceleration in relativistic shocks of electron-positron plasmas with proton admixture is investigated through two-dimensional (2D) particle-in-cell (PIC) simulations. The upstream plasma, with a bulk Lorentz factor of $10$ and a…

We investigate non-thermal emission from the Fermi bubbles on a hadronic model. Cosmic-ray (CR) protons are accelerated at the forward shock of the bubbles. They interact with the background gas in the Galactic halo and create $\pi^0$-decay…

We present a detailed, two dimensional numerical study of the microphysical conditions and dynamical evolution of accretion disks around black holes when neutrino emission is the main source of cooling. Such structures are likely to form…

We consider electron acceleration by obliquely propagating fast mode waves in magnetically dominated accretion disk coronae. For low coronal plasma densities, acceleration can exceed Coulomb drag at lower energies and energize electrons out…

We show that accretion disks with relativisticly hot electrons which are coupled to cold ions is subject to inertial-type instability in which kinematic drag between electrons and ions produces radial acceleration of electrons.

We investigate the acceleration of particles via the second-order Fermi process in the lobes of giant radio galaxies. Such sites are candidates for the accelerators of ultra-high energy cosmic rays. We focus on the nearby FR I radio galaxy…

Relativistic electrons colliding with intense counterpropagating laser pulses are expected to lose energy through radiation reaction. However, we reveal a counterintuitive regime where reflected leptons (including incident electrons,…

Magnetic fields are important for accretion disc structure. Magnetic fields in a disc system may be transported with the accreted matter. They can be associated with either the central body and/or jet, and be fossil or dynamo excited in…

We investigate acceleration and propagation processes of high-energy particles inside hot accretion flows. The magnetorotational instability (MRI) creates turbulence inside accretion flows, which triggers magnetic reconnection and may…

We investigate self-consistent particle acceleration near a pulsar polar cap (PC) by the electrostatic field due to the effect of inertial frame dragging. Test particles gain energy from the electric field parallel to the open magnetic…

I present the elements of accretion-disc physics applied to active galactic nuclei. The accretion driving mechanisms are discussed, then models of geometrically-thin discs, both stationary and time-dependent, are addressed. Disc's…

In addition to the ponderomotive acceleration of highly relativistic electrons at interaction of very short and very intense laser pulses, a further acceleration is derived from the interaction of these electron beams with the spontaneous…

A synthesis of the present knowledge on gamma-ray emission from the magnetosphere of a rapidly rotating neutron star is presented, focusing on the electrodynamics of particle accelerators. The combined curvature, synchrotron, and…

Most of the luminosity of accreting black hole is emitted in the X-ray band. This radiation is believed to emerge, through inverse Compton process, from a hot (Te ~ 10^8 -10^9 K) optically thin (Thomson optical depth ~ 1) plasma probably…

Particle-in-cell (PIC) simulations of collisionless jets of electrons and positrons in an ambient electron-proton plasma have revealed an acceleration of positrons at the expense of electron kinetic energy. The dominant instability within…

We investigate acceleration of cosmic rays by shocks and accretion flows in galaxy clusters. Numerical results for spectra of accelerated particles and nonthermal emission are presented. It is shown that the acceleration of protons and…