Related papers: Relativistic electron beams accelerated by an inte…
The early acceleration of protons and electrons in the nonrelativistic collisionless shocks with three obliquities are investigated through 1D particle-in-cell simulations. In the simulations, the charged particles possessing a velocity of…
We present a detailed investigation of the shock properties associated with solar energetic particle (SEP) events that exhibit a concave (``nose-like'') shape in their energy spectrogram, characterized by inverse velocity arrival (IVA) of…
It is shown that ions can be accelerated to MeV energy range in the direction perpendicular to the magnetic field by the ExB mechanism of electrostatic waves. The acceleration occurs in discrete steps of duration being a small fraction the…
Interplanetary Coronal Mass Ejection (ICME) shocks are known to accelerate particles and contribute significantly to Solar Energetic Particle (SEP) events. We have performed Magnetohydrodynamic-Particle in Cell (MHD-PIC) simulations of ICME…
Magnetic reconnection in relativistic collisionless plasmas can accelerate particles and power high-energy emission in various astrophysical systems. Whereas most previous studies focused on relativistic reconnection in pair plasmas, less…
Solar Orbiter, a mission developed by the European Space Agency, explores in situ plasma across the inner heliosphere while providing remote-sensing observations of the Sun. Our study examines particle observations for the 30 October 2021…
Astrophysical shocks create cosmic rays by accelerating charged particles to relativistic speeds. However, the relative contribution of various types of shocks to the cosmic ray spectrum is still the subject of ongoing debate. Numerical…
We present Particle-in-Cell simulation results of relativistic shear boundary layers between electron-ion and electron-positron plasmas and discuss their potential applications to astrophysics. Specifically, we find in the case of a fast…
Achieving high-quality electron beams from laser-plasma accelerators critically relies on density tailoring to control electron dynamics during injection, acceleration, and extraction. We report on the experimental observation of electron…
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…
Electron acceleration associated with various plasma kinetic instabilities in a nonrelativistic, very-high-Alfv\'en Mach-number ($M_A \sim 45$) shock is revealed by means of a two-dimensional fully kinetic PIC simulation. Electromagnetic…
Laser-plasma technology promises a drastic reduction of the size of high energy electron accelerators. It could make free electron lasers available to a broad scientific community, and push further the limits of electron accelerators for…
The understanding of the particle spectra resulting from acceleration in relativistic shocks as they occur in extragalactic sources, is essential for the interpretation of the cosmic ray spectrum above the ankle ($E_p>3\cdot 10^{18}$ eV).…
We present the first observational evidence of the irregular surface of interplanetary (IP) shocks by using multi-spacecraft observations of the Cluster mission. In total we discuss observations of four IP shocks that exhibit moderate…
We show that monoenergetic ion beams can be accelerated by moderate Mach number collisionless, electrostatic shocks propagating in a long scale-length exponentially decaying plasma profile. Strong plasma heating and density steepening…
An algorithm is demonstrated that performs first-principles tracking of relativistic charged-particles. A covariant approach is used which relies on retarded vector potentials for trajectory integration instead of performing electromagnetic…
It is well known that collisionless shocks are major sites of particle acceleration in the Universe, but the details of the acceleration process are still not well understood. The particle acceleration rate, which can shed light on the…
It is thought that solar energetic ions associated with coronal/interplanetary shock waves are accelerated to high energies by the diffusive shock acceleration mechanism. For this mechanism to be efficient, intense magnetic turbulence is…
Collisionless shocks are common features in space and astrophysical systems where supersonic plasma flows interact, such as in the solar wind, the heliopause, and supernova remnants. Recent experimental capabilities and diagnostics allow…
Recent experimental and theoretical results have demonstrated the possibility of accelerating electrons in the MeV range by focusing tightly a few-cycle laser beam in ambient air. Using Particle-In-Cell (PIC) simulations, this configuration…