Related papers: The termination shock in a striped pulsar wind
The observed energy spectra of accelerated particles at interplanetary shocks often do not match the diffusive shock acceleration (DSA) theory predictions. In some cases, the particle flux forms a plateau over a wide range of energies,…
Context. Plasma inflows accompany a variety of processes in the solar atmosphere such as heating of coronal loops and formation of prominences. Aims. We model a stratified solar atmosphere, within which a simulated prominence thread…
The energy lost by a rotation-powered pulsar is carried by a relativistic flow containing a mixture of electromagnetic fields and particles. In the inner regions, this is thought to be a magnetically dominated, cold, electron-positron wind…
Shock acceleration is considered one of the most important mechanisms for the acceleration of astrophysical energetic particles. In this work, we calculate the trajectories of a large number of test charged particles accurately in a…
Nonthermal loop-top sources in solar flares are the most prominent observational signature that suggests energy release and particle acceleration in the solar corona. Although several scenarios for particle acceleration have been proposed,…
Particle acceleration consequences from fluctuating electric fields superposed on an X-type magnetic field in collisionless solar plasma are studied. Such a system is chosen to mimic generic features of dynamic reconnection, or the…
The shock waves produce relativistic particles via the diffusive shock acceleration (DSA) mechanism. Among various circumstances, fast acceleration has been expected for perpendicular shocks. We investigate the acceleration time and the…
The conversion of magnetic energy into other forms during solar flares is one of the outstanding open problems in solar physics. It is generally accepted that magnetic reconnection plays a crucial role in these conversion processes. To…
We determine the spectrum of particles accelerated at shocks with arbitrary speed and arbitrary scattering properties for different choices of the equation of state of the downstream plasma. More specifically we consider the effect of…
We present measurements from the ESA/NASA Cluster mission that show in situ acceleration of ions to energies of 1 MeV outside the bow shock. The observed heating can be associated with the presence of electromagnetic structures with strong…
Since the launch of the Fermi telescope more than five years ago, many new gamma-ray pulsars have been discovered with intriguing properties challenging our current understanding of pulsar physics. Observation of the Crab pulsar furnish…
We review here some magnetic phenomena in astrophysical particle accelerators associated with collisionless shocks in supernova remnants, radio galaxies and clusters of galaxies. A specific feature is that the accelerated particles can play…
We suggest a physical mechanism whereby the acceleration time of cosmic rays by shock waves can be significantly reduced. This creates the possibility of particle acceleration beyond the knee energy at ~10^15eV. The acceleration results…
The emission of intense radio pulses by flaring magnetars is investigated. Small-scale current gradients can be imprinted into a strongly magnetized outflow by the same processes that source fireball radiation in the closed magnetosphere.…
Context. It has been suggested that collapsing magnetic traps may contribute to accelerating particles to high energies during solar flares. Aims. We present a detailed investigation of the energization processes of particles in collapsing…
The acceleration of charged particles by interplanetary shocks can drain a non-negligible fraction of the upstream ram pressure. For a sample of shocks observed in-situ at 1 AU by the ACE and Wind spacecraft, time-series of the…
Pulsar Wind Nebulae (PWNe) act as calorimeters for the relativistic pair winds emanating from within the pulsar light cylinder. Their radiative dissipation in various wavebands is significantly different from that of their pulsar central…
In addition to gamma-ray binaries which contain a compact object, high-energy and very high-energy gamma rays have also been detected from colliding-wind binaries. The collision of the winds produces two strong shock fronts, one for each…
In models of fast magnetic reconnection, flux transfer occurs within a small portion of a current sheet triggering stored magnetic energy to be thermalized by shocks. When the initial current sheet separates magnetic fields which are not…
Delayed radio flares of optical tidal disruption events (TDEs) indicate the existence of non-relativistic outflows accompanying TDEs. The interaction of TDE outflows with the surrounding circumnuclear medium creates quasi-perpendicular…