Related papers: Stellarator bootstrap current and plasma flow velo…
In this PhD thesis, a method for solving fast and accurately the monoenergetic drift-kinetic equation at low collisionality is presented. The algorithm is based on the analytical properties of the drift-kinetic equation when its dependence…
The conditions for the excitation of current and voltage oscillations in the plasma of a three-electrode current and voltage stabilizer are experimentally investigated. It was found that in the regimes under consideration, the plasma has…
We present a new method to estimate terminal bubble velocities during first-order phase transitions in a plasma in local equilibrium. The method relies on calculating the extrema of a modified potential function for the scalar field…
A long-standing debate in the literature about the kinetic form of the Bohm criterion is resolved for plasmas with single positive ion species when transport is dominated by charge exchange collisions. The solution of the Boltzmann equation…
The properties of a partially ionized plasma in a long cylindrical tube subject to a uniform axial electric field are investigated. The plasma is maintained by an external ionizing source balanced by bulk and surface recombinations.…
Poloidal and toroidal velocities of fully-ionised carbon are measured by means of charge exchange recombination spectroscopy (CXRS) in the TJ-II stellarator. We present a detailed treatment of the 3D geometry and show that flow…
The Rosenbluth form for the collision operator for a weakly relativistic plasma is derived. The formalism adopted by Antonsen and Chu can then be used to calculate the efficiency of current drive by fast waves in a relativistic plasma.…
The behaviour of a strongly-magnetized collisional electron-positron plasma which is optically thin to cyclotron radiation is considered, and the distribution functions accessible to it on the various timescales in the system are…
We obtain exact upper and lower bounds on the steady state drift velocity, and kinetic energy of electrons, driven by an external field in a weakly ionized plasma (swarm approximation). The scattering is assumed to be elastic with…
Modern particle accelerators and their applications increasingly rely on precisely coordinated interactions of intense charged particle and laser beams. Femtosecond-scale synchronization alongside micrometre-scale spatial precision are…
The dynamics of the true-vacuum bubbles nucleated during a first-order phase transition is affected by the distribution functions of the particle species in the plasma, driven out-of-equilibrium by the travelling domain wall. An accurate…
The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. In this formulation the collision operator is expressed in terms of five scalar potentials which are given by one-dimensional…
The drift kinetic equation is solved for low density TJ-II plasmas employing slowly varying, time-dependent profiles. This allows to simulate density ramp-up experiments and to describe from first principles the formation and physics of the…
First order phase transitions in the early universe may have left a variety of experimentally accessible imprints. The dynamics of such transitions is governed by the density perturbations caused by the propagation of the bubble wall in the…
Stellarator plasmas are externally controlled to a degree unparalleled by any other fusion concept, magnetic or inertial. This control is largely through the magnetic fields produced by external coils. The development of fusion energy could…
The energy budget of a collisionless plasma subject to electrostatic fluctuations is considered, and the excess of thermal energy over the minimum accessible to it under various constraints that limit the possible forms of plasma motion is…
Most plasmas have a very thin sheath compared with the plasma dimension. This necessitates separate calculations of the plasma and sheath. The Bohm criterion provides the boundary condition for calculation of plasma profiles. To calculate…
We argue that stochastic and resonant ion heating, often viewed as distinct processes in low-$\beta$ collisionless plasmas, are the far limits of a continuum controlled by nonlinear broadening of turbulent fluctuations, and thus by the…
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…
We explore analytically the structure of relativistic shock and solitary wave solutions in collisionless plasmas. In the wave frame of reference, a cold plasma is flowing from one end and impacting on a low velocity plasma. First we show…