Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 1510.06221

Monte Carlo method and High Performance Computing for solving Fokker-Planck equation of minority plasma particles

Eero Hirvijoki·Taina Kurki-Suonio·Simppa Äkäslompolo·Jari Varje·Tuomas Koskela·Juho Miettunen
View original source ↗Read source document ↗Export metadata ↓

Abstract

This paper explains how to obtain the distribution function of minority ions in tokamak plasmas using the Monte Carlo method. Since the emphasis is on energetic ions, the guiding-center transformation is outlined, including also the transformation of the collision operator. Even within the guiding-center formalism, the fast particle simulations can still be very CPU intensive and, therefore, we introduce the reader also to the world of high-performance computing. The paper is concluded with a few examples where the presented method has been applied.

Explore related subjects

physics.plasm-phphysics.comp-ph

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Eero Hirvijoki, Taina Kurki-Suonio, Simppa Äkäslompolo, Jari Varje, Tuomas Koskela, Juho Miettunen. 2015-10-21. Monte Carlo method and High Performance Computing for solving Fokker-Planck equation of minority plasma particles. https://doi.org/10.1017/s0022377815000203

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Scalable Terbium-149 Production from Highly Enriched Gadolinium-150 Targets

We propose a two-stage production method to overcome existing supply-constraints for the alpha-emitter $^{149\mathrm{g}}$Tb, a promising candidate for Targeted Alpha Therapy (TAT) with no existing globally scalable production pathway. Although awaiting experimental measurement of the $^{150}$Gd(p,2n)$^{149\mathrm{g}}$Tb cross section, the proposed method could produce $^{149\mathrm{g}}$Tb at clinical scale and beyond on readily available proton cyclotrons, enabled by production of the extinct but long-lived isotope $^{150}$Gd, a pure alpha emitter with a 1.79 million year half-life. Stage one generates $^{150}$Gd feedstock by irradiating natural Eu or enriched $^{151}$Eu with $\gtrsim$10 MeV protons, neutrons or photons. Stage two produces $^{149\mathrm{g}}$Tb from fabricated $^{150}$Gd targets by driving the $^{150}$Gd(p,2n)$^{149\mathrm{g}}$Tb reaction with $\gtrsim$14 MeV protons, accessible on over 700 reported cyclotrons worldwide. Fast fusion neutrons appear to offer the most scalable pathway for $^{150}$Gd production: even with a large $^{149 \mathrm{g}}$Tb dose size of 1 GBq and 40 million administered doses/yr, we estimate this would require neutrons produced by only 6.8 megawatts of steady-state deuterium-tritium power to produce the required $^{150}$Gd, far below expected capacity in the next decade. The route described here, if validated, would enable $^{149\mathrm{g}}$Tb supply at the scale needed to support clinical development of $^{149\mathrm{g}}$Tb-based TAT.

physics.plasm-ph↗
arXiv2026

Analytic toroidal 3D MHD equilibria and steady Euler flows with invariant surfaces

Families of explicit analytic solutions of the magnetohydrodynamic equilibrium equations are presented, equivalent to steady incompressible Euler flow. The solutions are non-axisymmetric and possess exact nested toroidal flux surfaces. No expansion is made in inverse aspect ratio or in the deviation from axisymmetry. The magnetic field and flux surfaces are given explicitly in Cartesian coordinates using elementary functions. The field, current density, and scalar pressure are smooth over the toroidal domain. The pressure gradient vanishes only on the magnetic axis. One family of solutions has uniform rotational transform $ι=2$, while another family has a sheared $ι$ profile. These counterexamples to Grad's conjecture are valuable for understanding the existence and regularity of 3D equilibria and for testing numerical codes.

physics.plasm-ph↗
arXiv2026

Dynamics of an impulse dielectric barrier discharge in pure ammonia gas using electrical characteristics and imaging analysis

A glow nanosecond discharge from a plane-to-plane impulse dielectric barrier discharge (iDBD) with ammonia gas has been characterised by employing fast imaging and electrical diagnostics. More precisely, the aim of this study is to investigate the dynamics of the discharge establishment under various conditions of applied voltage, pressure, and gas gap. The comparison between the current measurements and the image analysis exposes a strong correlation between the fast excitation and ionization wave velocity and the rising current velocity. This correlation has been found only for diffuse mode discharge since a front wave could be clearly defined, denoted as the luminous propagation front (LPF). Furthermore, this correlation is supported by a proportionality factor of 1.5 10$^{-3}$ which is systematic over the studied conditions. Further investigations are considered to evaluate the relevance of such a value over more parameters.

physics.plasm-ph↗