Related papers: Relativistic electron beams accelerated by an inte…
Intense laser-plasma interactions are an essential tool for the laboratory study of ion acceleration at a collisionless shock. With two-dimensional particle-in-cell calculations of a multicomponent plasma we observe two electrostatic…
The dynamics of relativistic electrons interacting with a laser pulse in a plasma wave has been investigated theoretically and numerically based on the classical Landau-Lifshitz equation. There exists a convergent trajectory of electrons…
Collisionless shocks are fundamental accelerators of energetic particles; yet, the observations of nonlinear foreshock structures, which are essential in acceleration processes, differ significantly between Interplanetary (IP) shocks and…
Compact acceleration of a tightly collimated relativistic electron beam with high charge from a laser-plasma interaction has many unique applications. However, currently the well-known schemes, including laser wakefield acceleration from…
We investigate the electrostatic acceleration of electrons and positrons in the vicinity of the event horizon, applying the pulsar outer-gap model to black hole magnetospheres. During a low accretion phase, the radiatively inefficient…
Particle acceleration is expected to be different between relativistic and non-relativistic collisionless shocks. We show that electromagnetic counterparts to gravitational waves (GWs), gamma-ray burst (GRB) afterglows, are ideal targets…
Relativistic astrophysical collisionless shocks represent outstanding dissipation agents of the huge power of relativistic outflows produced by accreting black holes, core collapsed supernovae and other objects into multi-messenger…
Relativistic collisionless shocks are believed to be efficient particle accelerators. Nonlinear outcome of the interaction of accelerated particles that run ahead of the shock, the so-called "precursor", with the unperturbed plasma of the…
Solar energetic particles in the heliosphere are produced by flaring processes on the Sun or shocks driven by coronal mass ejections. These particles are regularly detected remotely as electromagnetic radiation (X-rays or radio emission),…
Relativistic shocks are considered efficient accelerators of charged particles and play crucial roles in high-energy astrophysical phenomena, such as gamma-ray bursts and pulsar winds. This study focuses on positron accelerations in…
We present \emph{in situ} observations of the source regions of interplanetary (IP) type II radio bursts, using data from the Wind spacecraft during the period 1996-2002. We show the results of this survey as well as in-depth analysis of…
In this study, we present the first-ever direct measurements of synchrotron-emitting heliospheric traveling shocks, intercepted by the Parker Solar Probe (PSP) during its close encounters. Given that much of our understanding of powerful…
The excitation of surface plasmons with ultra-intense ($I\sim 5\times 10^{19}$ W/cm$^2$), high contrast ($\sim 10^{12}$) laser pulses on periodically-modulated solid targets has been recently demonstrated to produce collimated bunches of…
The plasma-based acceleration is an encouraging technique to overcome the limits of the accelerating gradient in the conventional RF acceleration. A plasma accelerator is able to provide accelerating fields up to hundreds of $GeV/m$, paving…
Pulsar Wind Nebulae are the astrophysical sources that host the most relativistic shocks in Nature and the only Galactic sources in which we have direct evidence of PeV particles. These facts make them very interesting from the point of…
We present a 2D kinematic model to study the acceleration of solar energetic particles (SEPs) at a shock driven by a coronal mass ejection. The shock is assumed to be spherical about an origin that is offset from the center of the Sun. This…
Plasma processes close to SNR shocks result in the amplification of magnetic fields and in the acceleration of electrons, injecting them into the diffusive acceleration mechanism. The acceleration of electrons and the B field amplification…
We report on the radio-emission characteristics of 222 interplanetary (IP) shocks. A surprisingly large fraction of the IP shocks (~34%) is radio quiet (i.e., the shocks lacked type II radio bursts). The CMEs associated with the RQ shocks…
We examine Fermi-type acceleration at relativistic shocks, and distinguish between the initial boost of the first shock crossing cycle, where the energy gain per particle can be very large, and the Fermi process proper with repeated shock…
In this work, a gradual solar energetic particle (SEP) event observed by multispacecraft has been simulated. The time profiles of SEP fluxes accelerated by an interplanetary shock in the three-dimensional interplanetary space are obtained…