PIC/MCC Simulations for the Oxygen Microwave Breakdown at Atmospheric Conditions

In this paper, the code of Particle-In-Cell/Monte Carlo Collision (PIC/MCC) for oxygen microwave breakdown is developed. This code is based on the three dimensional particle-in-cell platform CHIPIC, and with a module for increasing the charge of each super-particle. With this PIC/MCC code, the multiplication rate of the electron density and the delay time in oxygen breakdown at atmospheric conditions are researched. The results show: the multiplication rate of the electron density is periodic, and its period is the half of the electric field period; the breakdown delay time in the gas breakdown increases while the frequency of electric field or the gas pressure increases.

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Monte Carlo studies on electromagnetic cascades in extensive air showers

Canadian Journal of Physics ◽

10.1139/p68-205 ◽

1968 ◽

Vol 46 (10) ◽

pp. S189-S196 ◽

Cited By ~ 2

Author(s):

K. O. Thielheim ◽

E. K. Schlegel ◽

R. Beiersdorf

Keyword(s):

Monte Carlo ◽

Electron Density ◽

Three Dimensional ◽

High Energy ◽

Extensive Air Showers ◽

Air Showers ◽

Energy Distributions ◽

The Core ◽

Fragmentation Mechanisms ◽

Monte Carlo Studies

Three-dimensional Monte Carlo calculations have been performed on the trajectories of high-energy hadrons in extensive air showers. The central electron density and gradient of distribution are obtained for individual electromagnetic cascades together with coordinates at the level of observation. Various assumptions concerning primary mass number and energy, distributions of strong interaction parameters, and fragmentation mechanisms are discussed with respect to the production of steep maxima of electron density by single electromagnetic cascades in the core region of extensive air showers.

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Three-dimensional particle-in-cell with Monte Carlo collision simulation of the electron energy distribution function in the multi-cusp ion source for proton therapy

Chinese Physics C ◽

10.1088/1674-1137/36/10/018 ◽

2012 ◽

Vol 36 (10) ◽

pp. 1013-1018

Author(s):

Chao Yang ◽

Xiao-Bing Wu ◽

Da-Gang Liu

Keyword(s):

Monte Carlo ◽

Distribution Function ◽

Energy Distribution ◽

Electron Energy ◽

Proton Therapy ◽

Electron Energy Distribution Function ◽

Three Dimensional ◽

Ion Source ◽

Energy Distribution Function ◽

Particle In Cell

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Particle acceleration in a reconnecting current sheet: PIC simulation

Journal of Plasma Physics ◽

10.1017/s0022377809008009 ◽

2009 ◽

Vol 75 (5) ◽

pp. 619-636 ◽

Cited By ~ 22

Author(s):

TARAS V. SIVERSKY ◽

VALENTINA V. ZHARKOVA

Keyword(s):

Electric Field ◽

Energy Distribution ◽

Current Sheet ◽

Plasma Density ◽

Three Dimensional ◽

Polarization Field ◽

Electron Mass ◽

Langmuir Waves ◽

Particle In Cell ◽

Reconnecting Current Sheet

AbstractThe acceleration of protons and electrons in a reconnecting current sheet (RCS) is simulated with a particle-in-cell (PIC) 2D3V (two-dimensional in space and three-dimensional in velocity space) code for the proton-to-electron mass ratio of 100. The electromagnetic configuration forming the RCS incorporates all three components of the magnetic field (including the guiding field) and a drifted electric field. PIC simulations reveal that there is a polarization electric field that appears during acceleration owing to a separation of electrons from protons towards the midplane of the RCS. If the plasma density is low, the polarization field is weak and the particle trajectories in the PIC simulations are similar to those in the test particle (TP) approach. For the higher plasma density the polarization field is stronger and it affects the trajectories of protons by increasing their orbits during acceleration. This field also leads to a less asymmetrical abundance of ejected protons towards the midplane in comparison with the TP approach. For a given magnetic topology electrons in PIC simulations are ejected to the same semispace as protons, in contrast to the TP results. This happens because the polarization field extends far beyond the thickness of a current sheet. This field decelerates the electrons, which are initially ejected into the semispace opposite to the protons, returns them back to the RCS, and, eventually, leads to the electron ejection into the same semispace as protons. The energy distribution of the ejected electrons is rather wide and single-peaked, in contrast to the two-peak narrow-energy distribution obtained in the TP approach. In the case of a strong guiding field, the mean energy of the ejected electrons is found to be smaller than it is predicted analytically and by the TP simulations. The beam of accelerated electrons is also found to generate turbulent electric field in the form of Langmuir waves.

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Effects on magnetic reconnection of a density asymmetry across the current sheet

Annales Geophysicae ◽

10.5194/angeo-26-2471-2008 ◽

2008 ◽

Vol 26 (8) ◽

pp. 2471-2483 ◽

Cited By ~ 54

Author(s):

K. G. Tanaka ◽

A. Retinò ◽

Y. Asano ◽

M. Fujimoto ◽

I. Shinohara ◽

...

Keyword(s):

Magnetic Field ◽

Electric Field ◽

Magnetic Reconnection ◽

Current Sheet ◽

Three Dimensional ◽

Flow Region ◽

Electron Acceleration ◽

Particle In Cell ◽

Line Structure ◽

Simulation Results

Abstract. The magnetopause (MP) reconnection is characterized by a density asymmetry across the current sheet. The asymmetry is expected to produce characteristic features in the reconnection layer. Here we present a comparison between the Cluster MP crossing reported by Retinò et al. (2006) and virtual observations in two-dimensional particle-in-cell simulation results. The simulation, which includes the density asymmetry but has zero guide field in the initial condition, has reproduced well the observed features as follows: (1) The prominent density dip region is detected at the separatrix region (SR) on the magnetospheric (MSP) side of the MP. (2) The intense electric field normal to the MP is pointing to the center of the MP at the location where the density dip is detected. (3) The ion bulk outflow due to the magnetic reconnection is seen to be biased towards the MSP side. (4) The out-of-plane magnetic field (the Hall magnetic field) has bipolar rather than quadrupolar structure, the latter of which is seen for a density symmetric case. The simulation also showed rich electron dynamics (formation of field-aligned beams) in the proximity of the separatrices, which was not fully resolved in the observations. Stepping beyond the simulation-observation comparison, we have also analyzed the electron acceleration and the field line structure in the simulation results. It is found that the bipolar Hall magnetic field structure is produced by the substantial drift of the reconnected field lines at the MSP SR due to the enhanced normal electric field. The field-aligned electrons at the same MSP SR are identified as the gun smokes of the electron acceleration in the close proximity of the X-line. We have also analyzed the X-line structure obtained in the simulation to find that the density asymmetry leads to a steep density gradient in the in-flow region, which may lead to a non-stationary behavior of the X-line when three-dimensional freedom is taken into account.

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