Evaluation of the first Coulomb Bridge in three dimensions

Journal of Computational Physics, 2013

Both binary and grid-based Langevin equations models for Coulomb collisions are used in particle simulation of plasmas. We introduce a variant of the conventional binary collision algorithm for performing Coulomb collisions. In this algorithm particles in a configuration space cell are not paired for collisions. Instead, for every test particle in the cell, a unique field particle is defined by randomly sampling a velocity distribution defined on the grid by accumulating moments of the particle distribution function(s). The test and field particle pair then undergoes a collision using the standard methodology for binary collisions. The performance of the new algorithm is illustrated in example computations and compared to a drag-diffusion Langevin equations algorithm. The grid-based algorithms do not conserve momentum and energy, although with good particle statistics the non-conservation is relatively small. Conservation can be restored after collisions using a shift and scaling of the momenta. The comparative merits of the new algorithm are discussed.

Journal of Physics: Conference Series, 2005

Spherically symmetric three-dimensional charged particle clusters are analyzed experimentally and theoretically. Based on accurate molecular dynamics simulations ground state configurations and energies with clusters for N ≤ 160 are presented which correct previous results of Hasse and Avilov [Phys. Rev. A 44, 4506 (1991)]. A complete table is given in the appendix. Further, the lowest metastable states are analyzed.

حوليات العلوم و التكنولوجيا, 2013

In this work, we calculated the effective potential of an electron in a plasma. This potential, which is obtained by solving a non-linear integral equation, is a sum of three contributions: the first is the interaction energy between the electron plasma and a test charge regarded as an impurity. We have taken this interaction equal to screened "Kelbg". The second is the Coulomb interaction energy between the electron in question and the other electrons plasma, that we calculate using a Maxwell-Boltzmann distribution. The third is Coulomb interaction energy between the electron and ions plasma uniformly distributed. The effective potential, is obtained, in the first stage, we have calculated the distribution of electric microfield created by the electrons on the impurity. In the second stage we calculated the time autocorrelation function of the electric microfield. The results are compared with those given by molecular dynamics simulation.

Shabd Publication, 2020

Plasma is a set of neutral and charged particles which reveals a number of collective behaviors. The very long range coulomb forces enable the charged particles in plasma to work together with one another simultaneously. The study of plasma is actually a really ancient area of investigation in plasma physics and it remains to be among the vital fields due to the crucial role of its in most plasma uses including plasma processing, fabrication of semiconductor systems, etching, etc. except the presence of just ions and electrons, the plasma in many instances, has a number of other species of ions like negative ions which impact the complete plasma behaviour. Within this paper we study about the fundamental ideas of plasma physics.

Atoms, 2014

In weakly coupled plasmas, it is common to describe the microfield using a Debye model. We examine here an "artificial" ideal one-component plasma with an infinite Debye length, which has been used for the test of line shape codes. We show that the infinite Debye length assumption can lead to a misinterpretation of numerical simulations results, in particular regarding the convergence of calculations. Our discussion is done within an analytical collision operator model developed for hydrogen line shapes in near-impact regimes. When properly employed, this model can serve as a reference for testing the convergence of simulations.

Contributions to Plasma Physics, 2014

1998

The one-component plasma (OCP) represents the simplest statistical mechanical model of a Coulomb system. For this reason, it has been extensively studied over the last 40 years. The advent of the integral equations has resulted in a dramatic improvement in our ability to carry out numerical calculations, but came at the expense of a physical insight gained in a simpler analytic theory. In this paper we present an extension of the Debye-Hückel (DH) theory to the OCP. The theory allows for analytic calculations of all the thermodynamic functions, as well as the structure factor. The theory explicitly satisfies the Stillinger-Lovett and, for small couplings, the compressibility sum rules, implying its internal self consistency.

1996

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Contributions to Plasma Physics, 2015

In this paper the relaxation properties of non-isothermal dense plasmas were studied. Based on the effective interaction potentials between particles, the Coulomb logarithm for two-temperature non-isothermal dense plasmas was obtained. These potentials take into consideration long-range multi-particle screening effects and short-range quantum-mechanical effects in two-temperature plasmas. The relaxation processes in such plasmas were studied using the Coulomb logarithm. The obtained results were compared with theoretical works of other authors and with the results of molecular dynamics simulation.

arXiv (Cornell University), 2021

The 3-D exact analytical solutions of ideal two fluid plasma, single fluid plasma (MHD) and neutral fluid equations have been found using physically justifiable assumptions. Surprisingly these solutions satisfy all non-linearities in the systems. It is pointed out that these solutions explain the fundamental mechanism behind the creation of vast variety of ordered structures in plasmas and fluids. In the limiting case of two dimensional (2-D) dependence of fields, the theoretical model for plasma is applied to explain the formation of spicules in solar chromosphere. It is pointed out that the main contribution of electron (ion) baro clinic vectors is to produce vorticity in the plasma and that magnetic field generation is coupled with the flow of both electrons and ions.