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Related papers: Bump formation in the runaway electron tail

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Runaway electrons, which are generated in a plasma where the induced electric field exceeds a certain critical value, can reach very high energies in the MeV range. For such energetic electrons, radiative losses will contribute…

Plasma Physics · Physics 2017-03-10 E. Hirvijoki , I. Pusztai , J. Decker , O. Embréus , A. Stahl , T. Fülöp

Runaway electrons (REs) can be generated in tokamak plasmas if the accelerating force from the toroidal electric field exceeds the collisional drag force due to Coulomb collisions with the background plasma. In ITER, disruptions are…

Plasma Physics · Physics 2015-03-23 E. Nilsson , J. Decker , Y. Peysson , R. S. Granetz , F. Saint-Laurent , M. Vlainic

A new physical mechanism of formation of runaway electron (RE) beams during plasma disruptions in tokamaks is proposed. The plasma disruption is caused by a strong stochastic magnetic field formed due to nonlinearly excited low-mode number…

The wake behind a large object (such as the moon) moving rapidly through a plasma (such as the solar wind) contains a region of depleted density, into which the plasma expands along the magnetic field, transverse to the flow. It is shown…

Space Physics · Physics 2015-05-30 I. H. Hutchinson

Runaway electron loads onto material structures are a major concern for future large tokamaks due to the efficient avalanching at high plasma currents. Here, we perform predictive studies using the JOREK code for a plausible plasma…

We consider the Landau-Coulomb equation for a (hydrogen) plasma heated by an external electric field. In this setting, theoretical and experimental results in plasma physics show the emergence of so-called \emph{runaway electrons} which are…

Analysis of PDEs · Mathematics 2026-05-15 Ling-Bing He , Richard M. Höfer , Jie Ji , Raphael Winter

Generation of anomalously energetic suprathermal electrons was observed in simulation of a high- voltage dc discharge with electron emission from the cathode. An electron beam produced by the emission interacts with the nonuniform plasma in…

Plasma Physics · Physics 2016-01-20 D. Sydorenko , I. D. Kaganovich , L. Chen , P. L. G. Ventzek

We present test-particle simulations of electrons during a nonlinear MHD simulation of a type-I edge localized mode (ELM) to explore the effect of an eruptive plasma filament on the kinetic level. The electrons are moderately heated and…

Plasma Physics · Physics 2022-11-23 Heinz Isliker , Andres Cathey , Matthias Hoelzl , Stanislas Pamela , Loukas Vlahos

Based on the analysis of data from the numerous dedicated experiments on plasma disruptions in the TEXTOR tokamak the mechanisms of the formation of runaway electron beams and their losses are proposed. The plasma disruption is caused by…

Driven by recent RHESSI observations of confined loop-top hard X-ray sources in solar flares, we consider stochastic acceleration of electrons in the presence of Coulomb collisions. If electron escape from the acceleration region can be…

Solar and Stellar Astrophysics · Physics 2015-06-23 Nicolas H. Bian , A. Gordon Emslie , Duncan J. Stackhouse , Eduard P. Kontar

Dynamics of an electron beam head-on colliding with an ultraintense focused ultrashort circularly-polarized laser pulse are investigated in the quantum radiation-dominated regime. Generally, the ponderomotive force of the laser fields may…

Plasma Physics · Physics 2018-11-21 Yan-Fei Li , Yong-Tao Zhao , Karen Z. Hatsagortsyan , Christoph H. Keitel , Jian-Xing Li

The problem of self-consistently coupling kinetic runaway-electron physics to the macroscopic evolution of the plasma is addressed by dividing the electron population into a bulk and a tail. A probabilistic closure is adopted to determine…

Plasma Physics · Physics 2018-08-01 Eero Hirvijoki , Chang Liu , Guannan Zhang , Diego del-Castillo-Negrete , Dylan Brennan

Runaway electrons with strongly anisotropic distributions present in post-disruption tokamak plasmas can destabilize the extraordinary electron (EXEL) wave. The present work investigates the dynamics of the quasi-linear evolution of the…

Plasma Physics · Physics 2015-02-26 G. I. Pokol , A. Kómár , A. Budai , A. Stahl , T. Fülöp

The formation of a substantial post-disruption runaway electron current in ASDEX Upgrade material injection experiments is determined by avalanche multiplication of a small seed population of runaway electrons. For the investigation of…

A simple model of cosmic ray electron acceleration at the jet boundary (Ostrowski 2000) yields a power-law particle energy distribution of ultrarelativistic electrons with an energy cut-off growing with time and finally, a growing particle…

Astrophysics · Physics 2009-11-07 L. Stawarz , M. Ostrowski

Runaway particles can be produced in plasmas with large electric fields. Here we address the possibility that such runaway ions and electrons excite Alfv\'enic instabilities. The magnetic perturbation induced by these modes can enhance the…

Plasma Physics · Physics 2015-06-19 T Fülöp , S Newton

This work explores for the first time bump-on-tail (BOT) instability excited by energetic electrons in helicon plasma. The Berk-Breizman model that developed for the wave-particle interaction and resulted instability in magnetic fusion is…

Synchrotron emission from runaway electrons may be used to diagnose plasma conditions during a tokamak disruption, but solving this inverse problem requires rapid simulation of the electron distribution function and associated synchrotron…

Plasma Physics · Physics 2014-03-31 Matt Landreman , Adam Stahl , Tünde Fülöp

Mitigation of runaway electrons is one of the outstanding issues for the reliable operation of ITER and other large tokamaks, and accurate estimates for the expected runaway-electron energies and current are needed. Previously, linearized…

Plasma Physics · Physics 2016-12-21 A. Stahl , O. Embréus , M. Landreman , G. Papp , T. Fülöp

Electron beam (e-beam) generated plasmas with applied crossed electric and magnetic $\left(\mathbf{E} \times \mathbf{B}\right)$ fields are promising for low damage processing of materials with applications to microelectronics and quantum…

Plasma Physics · Physics 2024-06-18 Nirbhav Singh Chopra , Ivan Romadanov , Yevgeny Raitses
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