Related papers: Ion dynamics and acceleration in relativistic shoc…
Understanding the conditions conducive to particle acceleration at collisionless, non-relativistic shocks is important for the origin of cosmic rays. We use hybrid (kinetic ions -- fluid electrons) kinetic simulations to investigate…
The strong influence of the electron dynamics provides the possibility of controlling the expansion of laser-produced plasmas by appropriately shaping the laser pulse. A simple irradiation scheme is proposed to tailor the explosion of large…
In this work, we investigate collisionless shocks propagating in a relativistically hot unmagnetized electron-positron plasmas. We estimate the dissipation fraction at shocks in the relativistically hot plasma, showing that it is…
Energetic particles are ubiquitous in space and astrophysical plasmas, and interplanetary shocks are widely regarded as one of the main particle accelerators in the heliosphere. Indeed, in-situ measurements typically show that energetic…
We have investigated particle acceleration and shock structure associated with an unmagnetized relativistic jet propagating into an unmagnetized plasma. Strong magnetic fields generated in the trailing jet shock lead to transverse…
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…
We discuss 3D simulations of relativistic collisionless shocks in electron-positron pair plasmas using the particle-in-cell (PIC) method. The shock structure is mainly controlled by the shock's magnetization ("sigma" parameter). We…
When two plasmas collide, their interaction can be mediated by collisionless plasma instabilities or binary collisions between particles of each shell. By comparing the maximum growth rate of the collisionless instabilities with the…
Collisionless shock acceleration, which transfers localized particle energies to non-thermal energetic particles via electromagnetic potential, is ubiquitous in space plasma. We investigate dynamics of collisionless electrostatic shocks…
The study of collisionless shocks and their role in cosmic ray acceleration has gained importance through observations and simulations, driving interest in reproducing these conditions in laboratory experiments using high-power lasers. In…
In this paper, we study shock structures of collisionless shocks in partially ionized plasmas by means of two-dimensional hybrid simulations, where the shock is a perpendicular shock with shock velocity Vsh ~ 40 Va ~ 1333 km/s and the…
Hot-cold ablative mixing plasmas are ubiquitous in astrophysical and laboratory systems, where a cold/dense plasma is roughly in pressure balance with a hot/dilute plasma. Examples include the plasma thermal quench during major disruptions…
Particle acceleration by means of non-linear plasma wave interactions is of great topical interest. Accordingly, in this paper we focus on the electron surfing process. Self-consistent kinetic simulations, using both relativistic Vlasov and…
Plasma wakefield acceleration is a groundbreaking technique for accelerating particles, capable of sustaining gigavolt-per-meter accelerating fields. Understanding the physical mechanisms governing the recovery of plasma accelerating…
Gamma ray bursts are among the most energetic events in the known universe. A highly relativistic fireball is ejected. In most cases the burst itself is followed by an afterglow, emitted under deceleration as the fireball plunges through…
Collisionless, turbulent plasmas surround the Earth, from the magnetosphere to the intergalactic medium, and the fluctuations within them affect nearly every field in the space sciences, from space weather forecasts to theories of galaxy…
Collisionless shocks generated by two colliding relativistic electron-positron plasma shells are studied using particle-in-cell (PIC) simulations. Shocks are mediated by the Weibel instability (WI), and the kinetic energy of the fastest…
When supersonic plasma flows collide, many physical processes contribute to the morphology of the resulting shock. One of these processes is the acceleration of non-thermal ions, which will, eventually, reach relativistic speeds and become…
We investigate the process of Diffusive Shock Acceleration (DSA) of particles with mass number to charge number ratios $A/Q > 1$, e.g., partially-ionized heavy ions. To this end, we introduce helium- and carbon-like ions at solar abundances…
Magnetic reconnection is a fundamental plasma process that is thought to play a key role in the production of nonthermal particles associated with explosive phenomena in space physics and astrophysics. Experiments at high-energy-density…