Small-angle Coulomb collision model for particle-in-cell simulations

Lemons, Don S.; Winske, D.; Daughton, W.; Albright, B. J.

doi:10.1016/j.jcp.2008.10.025

Cited by 58 publications

(68 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The z-axis in (1) coincides with the velocity vector of the test particle in the local mean drift frame of the field particles before the test particle is collisionally scattered. The scattered velocity vector is transformed back to the laboratory Cartesian frame with the rotation matrix given in [1] or [6], and the local mean drift of the field particles is added. Equation (1) is a discretized solution of the Fokker-Planck equation for the probability density of velocities f (v)…”

Section: Collision Algorithms In Particle Codesmentioning

confidence: 99%

“…In (19) of Manheimer et al, [4] a finite Δt correction to the drag F d is introduced to improve energy conservation. Energy and momentum conservation can be repaired by scaling and shifting velocities after the Monte Carlo collisions occur on each time step [4], [6].…”

Section: Collision Algorithms In Particle Codesmentioning

confidence: 99%

“…A variant of the grid-based Langevin-equations Coulomb collision operator has been introduced by Lemons et al [6]. The methodology in [6] scatters the velocity vector of the test particle using spherical polar coordinates (v, θ, φ).…”

Section: Collision Algorithms In Particle Codesmentioning

confidence: 99%

“…We show that one of the two grid-based Langevin equations models investigated has an unfavorable mass-ratio scaling such that modeling electronion collisions can require a much smaller time step than that 0093-3813/$26.00 © 2010 IEEE required using either the binary collision algorithm or a second Langevin equations algorithm that employs spherical polar velocity coordinates [6] in the example studied. This paper is organized as follows.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Time-Step Considerations in Particle Simulation Algorithms for Coulomb Collisions in Plasmas

Cohen

Dimits

Friedman

et al. 2010

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

Abstract-The accuracy of first-order Euler and higher-order time-integration algorithms for grid-based Langevin equations collision models in a specific relaxation test problem is assessed. We show that statistical noise errors can overshadow time-step errors and argue that statistical noise errors can be conflated with time-step effects. Using a higher-order integration scheme may not achieve any benefit in accuracy for examples of practical interest. We also investigate the collisional relaxation of an initial electron-ion relative drift and the collisional relaxation to a resistive steady-state in which a quasi-steady current is driven by a constant applied electric field, as functions of the time step used to resolve the collision processes using binary and grid-based, testparticle Langevin equations models. We compare results from two grid-based Langevin equations collision algorithms to results from a binary collision algorithm for modeling electron-ion collisions. Some guidance is provided on how large a time step can be used compared to the inverse of the characteristic collision frequency for specific relaxation processes.

show abstract

Section: Collision Algorithms In Particle Codesmentioning

confidence: 99%

Section: Collision Algorithms In Particle Codesmentioning

confidence: 99%

Section: Collision Algorithms In Particle Codesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Time-Step Considerations in Particle Simulation Algorithms for Coulomb Collisions in Plasmas

Cohen

Dimits

Friedman

et al. 2010

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

show abstract

“…The binary collision is then performed by using a semi-relativistic extension [13] of the Takizuka and Abe collision algorithm. The grid-based algorithm performs at least as good or better than other gridbased algorithms [14,15], is more tolerant to rare large Gaussian random number because only a scattering angle is determined by the random number, is not subject to possible noise-induced numerical instability [15], and allows use of a significantly larger time step for electron-ion collisions [13].…”

mentioning

confidence: 99%

A PIC-Fluid Hybrid Algorithm for Multiscale Simulations of Laser-Plasma Interactions

Cohen

Dimits

Divol

et al. 2014

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

ISR Spectra Simulations With Electron‐Ion Coulomb Collisions

et al. 2018

View full text Add to dashboard Cite

Incoherent scatter radars (ISR) rely on Thomson scattering of very high frequency or ultrahigh frequency radio waves off electrons in the ionosphere and measure the backscattered power spectra in order to estimate altitude profiles of plasma density, electron temperature, ion temperature, and ion drift speed. These spectra result from the collective behavior of coupled ion and electron dynamics, and, for most cases, existing theories predict these well. However, when the radar points nearly perpendicular to the Earth's magnetic field, the motion of the plasma across the field lines becomes complex and Coulomb collisions between electrons and ions become important in interpreting ISR measurements. This paper presents the first fully kinetic, self‐consistent, particle‐in‐cell simulations of ISR spectra with electron‐ion Coulomb collisions. We implement a grid‐based Coulomb collision algorithm in the Electrostatic Parallel Particle‐in‐Cell simulator and obtain ISR spectra from simulations both with and without collisions. For radar directions greater than 5° away from perpendicular to the magnetic field, both sets of simulations match collisionless ISR theory well. For angles between 3° and 5°, the collisional simulation is well described by a simplified Brownian motion collision process. At angles less than 3° away from perpendicular the Brownian motion model fails, and the collisional simulation qualitatively agrees with previous single particle simulations. For radar directions exactly perpendicular to the magnetic field the simulated collisional spectra match those from the Brownian motion collision theory, in agreement with previous single particle simulations.

show abstract

Small-angle Coulomb collision model for particle-in-cell simulations

Cited by 58 publications

References 27 publications

Time-Step Considerations in Particle Simulation Algorithms for Coulomb Collisions in Plasmas

Time-Step Considerations in Particle Simulation Algorithms for Coulomb Collisions in Plasmas

A PIC-Fluid Hybrid Algorithm for Multiscale Simulations of Laser-Plasma Interactions

ISR Spectra Simulations With Electron‐Ion Coulomb Collisions

Contact Info

Product

Resources

About