Related papers: Particle acceleration in shearing flows: the case …
Radio galaxies have long been considered as potential sources of ultra-high-energy cosmic rays (UHECRs). Recent analyses of the UHECR spectrum, composition, and arrival directions indicate that the nearest radio galaxy, Centaurus A, could…
Recent observations by Parker Solar Probe (PSP) suggest that protons and heavier ions are accelerated to high energies by magnetic reconnection at the heliospheric current sheet (HCS). By solving the energetic particle transport equation in…
The alignment, ordering and rotation of elongated granular particles was studied in shear flow. The time evolution of the orientation of a large number of particles was monitored in laboratory experiments by particle tracking using optical…
It has been proposed that blazar jets are structured, with a fast spine surrounded by a slower sheath or layer. This structured jet model explains some properties of their emission and morphology. Because of their relative motion, the…
Many of the blazars observed by Fermi actually have the peak of their time-averaged gamma-ray emission outside the $\sim$ GeV Fermi energy range, at $\sim$ MeV energies. The detailed shape of the emission spectrum around the $\sim$ MeV peak…
Almost all sources of high energy particles and photons are associated with jet phenomena. Prominent sources of such highly relativistic outflows are pulsar winds and Active Galactic Nuclei. The current understanding of these jets assumes…
Laser-solid interaction can lead to the acceleration of protons to tens of MeV. Here, we show that a strong enhancement of this acceleration can be achieved by splitting the laser pulse to two parts of equal energy and opposite incidence…
Sudden jets of collimated plasma arise from many locations on the Sun, including active regions. The magnetic field along which a jet emerges is often open to interplanetary space, offering a clear "escape route" for any flare-accelerated…
The large scale jet of quasar 3C 273 has been observed in radio to $\gamma$ ray frequencies. Earlier the X-ray emission from knot A of this jet has been explained with inverse Compton scattering of the cosmic microwave background radiations…
We model the kiloparsec-scale synchrotron emission from jets in 10 Fanaroff-Riley Class I radio galaxies for which we have sensitive, high-resolution imaging and polarimetry from the Very Large Array. We assume that the jets are…
We analyse the influence of the stochastic particle acceleration for the evolution of the electron spectrum. We assume that all investigated spectra are generated inside a spherical, homogeneous source and also analyse the synchrotron and…
Observations suggest that relativistic particles play a fundamental role in the dynamics of jets emerging from active galactic nuclei as well as in their interaction with the intracluster medium. However, no general consensus exists…
While collisionless plasmas are ubiquitously present near astrophysical compact objects, the impact that their composition has on the high-energy emission is presently unknown. We present the first investigation of particle-acceleration…
We address the problem of particle acceleration in solar flares by fast modes which may be excited during the reconnection and undergo cascade and are subjected to damping. We extend the calculations beyond quasilinear approximation and…
We explore the spectral and polarization properties of photospheric emissions from stratified jets in which multiple components, separated by a sharp velocity shear regions, are distributed in lateral direction. Propagation of thermal…
Addition of particles to a viscoelastic suspension dramatically alters the properties of the mixture, particularly when it is sheared or otherwise processed. Shear-induced stretching of the polymers results in elastic stress that causes a…
A puzzling feature of the {\it Chandra}--detected quasar jets is that their X-ray emission decreases faster along the jet than their radio emission, resulting to an outward increasing radio to X-ray ratio. In some sources this behavior is…
We present the first radio emission simulations from high resolution three dimensional relativistic hydrodynamic jets, which allow for a study of the observational implications of the interaction between the jet and external medium. This…
Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to $\sim 1$ TeV. Although the jets are known to be ultimately powered…
A distinct thermal or quasi-thermal spectral component is occasionally observed in gamma-ray burst (GRB) prompt emission spectra. Taking GRB 090902B as a case study, we investigate its origin within a structured jet framework, in which the…