Phase-space dynamics of runaway electrons in magnetic fields

Guo, Zehua; McDevitt, Christopher Joseph; Tang, Xian-Zhu

doi:10.1088/1361-6587/aa5952

Title: Phase-space dynamics of runaway electrons in magnetic fields

Abstract

Dynamics of runaway electrons in magnetic fields are governed by the competition of three dominant physics: parallel electric field acceleration, Coulomb collision, and synchrotron radiation. Examination of the energy and pitch-angle flows reveals that the presence of local vortex structure and global circulation is crucial to the saturation of primary runaway electrons. Models for the vortex structure, which has an O-point to X-point connection, and the bump of runaway electron distribution in energy space have been developed and compared against the simulation data. Lastly, identification of these velocity-space structures opens a new venue to re-examine the conventional understanding of runaway electron dynamics in magnetic fields.

Authors:

^[1];

^[1]

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: Thu Feb 16 00:00:00 EST 2017

Research Org.:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC), Fusion Energy Sciences (FES)

OSTI Identifier:: 1364543

Report Number(s):: LA-UR-16-26162
Journal ID: ISSN 0741-3335

Grant/Contract Number:: AC52-06NA25396

Resource Type:: Accepted Manuscript

Journal Name:: Plasma Physics and Controlled Fusion

Additional Journal Information:: Journal Volume: 59; Journal Issue: 4; Journal ID: ISSN 0741-3335

Publisher:: IOP Science

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Magnetic Fusion Energy; runaway electron; synchrotron radiation; phase space

Citation Formats


                    Guo, Zehua, McDevitt, Christopher Joseph, and Tang, Xian-Zhu. Phase-space dynamics of runaway electrons in magnetic fields.  United States: N. p., 2017. 
Web.  doi:10.1088/1361-6587/aa5952.

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                    Guo, Zehua, McDevitt, Christopher Joseph, & Tang, Xian-Zhu. Phase-space dynamics of runaway electrons in magnetic fields.  United States.  https://doi.org/10.1088/1361-6587/aa5952

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                    Guo, Zehua, McDevitt, Christopher Joseph, and Tang, Xian-Zhu. Thu .  
"Phase-space dynamics of runaway electrons in magnetic fields".  United States.  https://doi.org/10.1088/1361-6587/aa5952.  https://www.osti.gov/servlets/purl/1364543.

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@article{osti_1364543,

  title        = {Phase-space dynamics of runaway electrons in magnetic fields},

  author       = {Guo, Zehua and McDevitt, Christopher Joseph and Tang, Xian-Zhu},

  abstractNote = {Dynamics of runaway electrons in magnetic fields are governed by the competition of three dominant physics: parallel electric field acceleration, Coulomb collision, and synchrotron radiation. Examination of the energy and pitch-angle flows reveals that the presence of local vortex structure and global circulation is crucial to the saturation of primary runaway electrons. Models for the vortex structure, which has an O-point to X-point connection, and the bump of runaway electron distribution in energy space have been developed and compared against the simulation data. Lastly, identification of these velocity-space structures opens a new venue to re-examine the conventional understanding of runaway electron dynamics in magnetic fields.},

  doi          = {10.1088/1361-6587/aa5952},

  journal      = {Plasma Physics and Controlled Fusion},

  number       = 4,

  volume       = 59,

  place        = {United States},

  year         = {Thu Feb 16 00:00:00 EST 2017},

  month        = {Thu Feb 16 00:00:00 EST 2017}

}

Copy to clipboard

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Works referencing / citing this record:

Resolving runaway electron distributions in space, time, and energy
journal, May 2018

Paz-Soldan, C.; Cooper, C. M.; Aleynikov, P.
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Title: Phase-space dynamics of runaway electrons in magnetic fields

Abstract

Citation Formats

An Observational Overview of Solar Flares journal, August 2011

Synchrotron radiation from a runaway electron distribution in tokamaks journal, September 2013

Numerical characterization of bump formation in the runaway electron tail journal, January 2016

Adjoint Fokker-Planck equation and runaway electron dynamics journal, January 2016

Growth and decay of runaway electrons above the critical electric field under quiescent conditions journal, February 2014

Relativistic limitations on runaway electrons journal, June 1975

Efficiency of current drive by fast waves journal, January 1985

Momentum–space structure of relativistic runaway electrons journal, June 1998

Runaway electron drift orbits in magnetostatic perturbed fields journal, March 2011

Damping of relativistic electron beams by synchrotron radiation journal, December 2001

Theory of runaway electrons in ITER: Equations, important parameters, and implications for mitigation journal, March 2015

Magnetic field threshold for runaway generation in tokamak disruptions journal, February 2009

Relativistic bounce-averaged quasilinear diffusion equation for low-frequency electromagnetic fluctuations journal, November 2001

The physics of gamma-ray bursts journal, January 2005

Chapter 3: MHD stability, operational limits and disruptions journal, June 2007

TOWARD A BETTER UNDERSTANDING OF THE GRB PHENOMENON: A NEW MODEL FOR GRB PROMPT EMISSION AND ITS EFFECTS ON THE NEW L i NT – E peak,i rest,NT RELATION journal, July 2015

Runaway electron mechanism of air breakdown and preconditioning during a thunderstorm journal, June 1992

JET ITER-like wall—overview and experimental programme journal, December 2011

Electron and Ion Runaway in a Fully Ionized Gas. I journal, July 1959

Theory for avalanche of runaway electrons in tokamaks journal, October 1997

Effective Critical Electric Field for Runaway-Electron Generation journal, March 2015

Theory of Two Threshold Fields for Relativistic Runaway Electrons journal, April 2015

Role of Bremsstrahlung Radiation in Limiting the Energy of Runaway Electrons in Tokamaks journal, June 2005

Runaway Electrons in a Plasma journal, September 1973

Radiation reaction induced non-monotonic features in runaway electron distributions journal, July 2015

The physics of gamma-ray bursts: by Bing Zhang, Cambridge, Cambridge University Press, 2019, 579 pp., $79.99 (hardback), ISBN 978-1-107-02761-9. Scope: monograph, Level: researchers journal, August 2020

The physics of gamma-ray bursts journal, August 1991

Efficiency of current drive by fast waves report, August 1984

Synchrotron radiation from a runaway electron distribution in tokamaks text, January 2013

The Physics of Gamma-Ray Bursts text, January 2004

Efficiency of Current Drive by Fast Waves text, January 2005

Resolving runaway electron distributions in space, time, and energy journal, May 2018

An Observational Overview of Solar Flares
journal, August 2011

Synchrotron radiation from a runaway electron distribution in tokamaks
journal, September 2013

Numerical characterization of bump formation in the runaway electron tail
journal, January 2016

Adjoint Fokker-Planck equation and runaway electron dynamics
journal, January 2016

Growth and decay of runaway electrons above the critical electric field under quiescent conditions
journal, February 2014

Relativistic limitations on runaway electrons
journal, June 1975

Efficiency of current drive by fast waves
journal, January 1985

Momentum–space structure of relativistic runaway electrons
journal, June 1998

Runaway electron drift orbits in magnetostatic perturbed fields
journal, March 2011

Damping of relativistic electron beams by synchrotron radiation
journal, December 2001

Theory of runaway electrons in ITER: Equations, important parameters, and implications for mitigation
journal, March 2015

Magnetic field threshold for runaway generation in tokamak disruptions
journal, February 2009

Relativistic bounce-averaged quasilinear diffusion equation for low-frequency electromagnetic fluctuations
journal, November 2001

The physics of gamma-ray bursts
journal, January 2005

Chapter 3: MHD stability, operational limits and disruptions
journal, June 2007

TOWARD A BETTER UNDERSTANDING OF THE GRB PHENOMENON: A NEW MODEL FOR GRB PROMPT EMISSION AND ITS EFFECTS ON THE NEW L _i ^NT – E _peak,i ^rest,NT RELATION
journal, July 2015

Runaway electron mechanism of air breakdown and preconditioning during a thunderstorm
journal, June 1992

JET ITER-like wall—overview and experimental programme
journal, December 2011

Electron and Ion Runaway in a Fully Ionized Gas. I
journal, July 1959

Theory for avalanche of runaway electrons in tokamaks
journal, October 1997

Effective Critical Electric Field for Runaway-Electron Generation
journal, March 2015

Theory of Two Threshold Fields for Relativistic Runaway Electrons
journal, April 2015

Role of Bremsstrahlung Radiation in Limiting the Energy of Runaway Electrons in Tokamaks
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Runaway Electrons in a Plasma
journal, September 1973

Radiation reaction induced non-monotonic features in runaway electron distributions
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The physics of gamma-ray bursts: by Bing Zhang, Cambridge, Cambridge University Press, 2019, 579 pp., $79.99 (hardback), ISBN 978-1-107-02761-9. Scope: monograph, Level: researchers
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report, August 1984

Synchrotron radiation from a runaway electron distribution in tokamaks
text, January 2013

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Efficiency of Current Drive by Fast Waves
text, January 2005

Resolving runaway electron distributions in space, time, and energy
journal, May 2018