Related papers: Density bump formation in a collisionless electros…
Collisionless plasma shock theory, which applies for example to the afterglow of gamma ray bursts, still contains key issues that are poorly understood. In this paper we study charged particle dynamics in a highly relativistic collisionless…
A new electron acceleration mechanism is identified that develops when a relativistically intense laser irradiates the wedge of an over-dense plasma. This induces a diffracted electromagnetic wave with a significant longitudinal electric…
We study the expansion of a cold, non-neutral ion plasma into the vacuum. The plasma is made from cold rubidium atoms in a magneto-optical trap (MOT) and is formed via ultraviolet photoionization. We employ time-delayed plasma extraction…
We describe a recently realized experiment producing the most spherical cavitation bubbles today. The bubbles grow inside a liquid from a point-plasma generated by a nanosecond laser pulse. Unlike in previous studies, the laser is focussed…
Ab-initio numerical study of collisionless shocks in electron-ion unmagnetized plasmas is performed with fully relativistic particle in cell simulations. The main properties of the shock are shown, focusing on the implications for particle…
The collision of two expanding plasma clouds is investigated, emphasizing instabilities and electron energization in the plasma mixing layer. This work is directly relevant to laboratory experiments with explosively-created laser or z-pinch…
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…
While the front of a fluid shock is a few mean-free-paths thick, the front of a collisionless shock can be orders of magnitude thinner. By bridging between a collisional and a collisionless formalism, we assess the transition between these…
Magnetic reconnection converts magnetic energy into thermal and kinetic energy in plasma. Among numerous candidate mechanisms, ion acoustic instabilities driven by the relative drift between ions and electrons, or equivalently electric…
A model for the condensation of a dusty plasma is constructed by considering the spherical shielding layers surrounding a dust grain test particle. The collisionless region less than a collision mean free path from the test particle is…
The dynamics of electron injection in the direct laser acceleration (DLA) regime was investigated by means of three-dimensional particle-in-cell simulations and theoretical analysis. It is shown that when an ultra-intense laser pulse…
This letter reports the first complete observation of magnetized collisionless shock precursors formed through the compression of Biermann-battery magnetic fields in laser produced plasmas. At OMEGA, lasers produce a supersonic CH plasma…
We consider formation of dissipationless shock waves in Bose-Einstein condensates with repulsive interaction between atoms. It is shown that big enough initial inhomogeneity of density leads to wave breaking phenomenon followed by…
The formation of plasma channels with nonuniformity of about +- 3.5% has been demonstrated. The channels had a density of 1.2x10^19 cm-3 with a radius of 15 um and with length >= 2.5 mm. The channels were formed by 0.3 J, 100 ps laser…
In the Universe matter outside of stars and compact objects is mostly composed of collisionless plasma. The interaction of a supersonic plasma flow with an obstacle results in collisionless shocks that are often associated with intense…
We study with a two-dimensional particle-in-cell simulation the stability of a discontinuity or piston, which separates an electron-positron cloud from a cooler electron-proton plasma. Such a piston might be present in the relativistic jets…
We study with a one-dimensional particle-in-cell (PIC) simulation the expansion of a pair cloud into a magnetized electron-proton plasma as well as the formation and subsequent propagation of a tangential discontinuity that separates both…
A study of collisionless external shocks in gamma-ray bursts is presented. The shock structure, electromagnetic fields, and process of electron acceleration are assessed by performing a self-consistent 3D particle-in-cell (PIC) simulation.…
We numerically simulate gravitational shock wave collisions in a holographic model dual to a non-conformal four-dimensional gauge theory. We find two novel effects associated to the non-zero bulk viscosity of the resulting plasma. First,…
This paper overviews experimental and numerical results on acceleration of narrow energy spread ion beams by an electrostatic collisionless shockwave driven by 1 um (Omega EP) and 10 um (UCLA Neptune Laboratory) lasers in near critical…