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Title: The Roles of Fluid Compression and Shear in Electron Energization during Magnetic Reconnection

Abstract

Particle acceleration in space and astrophysical reconnection sites is an important unsolved problem in studies of magnetic reconnection. Earlier kinetic simulations have identified several acceleration mechanisms that are associated with particle drift motions. Here, we show that, for sufficiently large systems, the energization processes due to particle drift motions can be described as fluid compression and shear, and that the shear energization is proportional to the pressure anisotropy of energetic particles. By analyzing results from fully kinetic simulations, we show that the compression energization dominates the acceleration of high-energy particles in reconnection with a weak guide field, and the compression and shear effects are comparable when the guide field is 50% of the reconnecting component. Spatial distributions of those energization effects reveal that reconnection exhausts, contracting islands, and island-merging regions are the three most important regions for compression and shear acceleration. This study connects particle energization by particle guiding-center drift motions with that due to background fluid motions, as in the energetic particle transport theory. It provides foundations for building particle transport models for large-scale reconnection acceleration such as those in solar flares.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [1]; ORCiD logo [3]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); New Mexico Consortium, Los Alamos, NM (United States)
  3. Space Science Inst., Boulder, CO (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); New Mexico Consortium, Los Alamos, NM (United States); Space Science Institute, Boulder, CO (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES); LANL Laboratory Directed Research and Development (LDRD) Program; National Aeronautics and Space Administration (NASA)
OSTI Identifier:
1463496
Report Number(s):
LA-UR-18-21317
Journal ID: ISSN 1538-4357; TRN: US1902308
Grant/Contract Number:  
AC52-06NA25396; SC0018240; NNH16AC60I
Resource Type:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 855; Journal Issue: 2; Journal ID: ISSN 1538-4357
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; acceleration of particles; accretion; accretion disks; magnetic reconnection; Sun; corona; flares

Citation Formats

Li, Xiaocan, Guo, Fan, Li, Hui, and Birn, Joachim. The Roles of Fluid Compression and Shear in Electron Energization during Magnetic Reconnection. United States: N. p., 2018. Web. doi:10.3847/1538-4357/aaacd5.
Li, Xiaocan, Guo, Fan, Li, Hui, & Birn, Joachim. The Roles of Fluid Compression and Shear in Electron Energization during Magnetic Reconnection. United States. https://doi.org/10.3847/1538-4357/aaacd5
Li, Xiaocan, Guo, Fan, Li, Hui, and Birn, Joachim. Fri . "The Roles of Fluid Compression and Shear in Electron Energization during Magnetic Reconnection". United States. https://doi.org/10.3847/1538-4357/aaacd5. https://www.osti.gov/servlets/purl/1463496.
@article{osti_1463496,
title = {The Roles of Fluid Compression and Shear in Electron Energization during Magnetic Reconnection},
author = {Li, Xiaocan and Guo, Fan and Li, Hui and Birn, Joachim},
abstractNote = {Particle acceleration in space and astrophysical reconnection sites is an important unsolved problem in studies of magnetic reconnection. Earlier kinetic simulations have identified several acceleration mechanisms that are associated with particle drift motions. Here, we show that, for sufficiently large systems, the energization processes due to particle drift motions can be described as fluid compression and shear, and that the shear energization is proportional to the pressure anisotropy of energetic particles. By analyzing results from fully kinetic simulations, we show that the compression energization dominates the acceleration of high-energy particles in reconnection with a weak guide field, and the compression and shear effects are comparable when the guide field is 50% of the reconnecting component. Spatial distributions of those energization effects reveal that reconnection exhausts, contracting islands, and island-merging regions are the three most important regions for compression and shear acceleration. This study connects particle energization by particle guiding-center drift motions with that due to background fluid motions, as in the energetic particle transport theory. It provides foundations for building particle transport models for large-scale reconnection acceleration such as those in solar flares.},
doi = {10.3847/1538-4357/aaacd5},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 855,
place = {United States},
year = {Fri Mar 09 00:00:00 EST 2018},
month = {Fri Mar 09 00:00:00 EST 2018}
}

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Works referenced in this record:

First-Order Particle Acceleration in Magnetically Driven Flows
journal, March 2016


Stochastic Acceleration by Multi-Island Contraction during Turbulent Magnetic Reconnection
journal, April 2013


The role of compressibility in energy release by magnetic reconnection
journal, August 2012

  • Birn, J.; Borovsky, J. E.; Hesse, M.
  • Physics of Plasmas, Vol. 19, Issue 8
  • DOI: 10.1063/1.4742314

Geospace Environmental Modeling (GEM) Magnetic Reconnection Challenge
journal, March 2001

  • Birn, J.; Drake, J. F.; Shay, M. A.
  • Journal of Geophysical Research: Space Physics, Vol. 106, Issue A3
  • DOI: 10.1029/1999JA900449

Particle acceleration at astrophysical shocks: A theory of cosmic ray origin
journal, October 1987


Spectral Energy Transfer and Dissipation of Magnetic Energy from Fluid to Kinetic Scales
journal, January 2007


Ultrahigh performance three-dimensional electromagnetic relativistic kinetic plasma simulation
journal, May 2008

  • Bowers, K. J.; Albright, B. J.; Yin, L.
  • Physics of Plasmas, Vol. 15, Issue 5
  • DOI: 10.1063/1.2840133

RHESSI LINE AND CONTINUUM OBSERVATIONS OF SUPER-HOT FLARE PLASMA
journal, December 2010


The Boltzmann equation an d the one-fluid hydromagnetic equations in the absence of particle collisions
journal, July 1956

  • Chew, G. F.; Goldberger, M. L.; Low, F. E.
  • Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, Vol. 236, Issue 1204, p. 112-118
  • DOI: 10.1098/rspa.1956.0116

The mechanisms of electron heating and acceleration during magnetic reconnection
journal, September 2014

  • Dahlin, J. T.; Drake, J. F.; Swisdak, M.
  • Physics of Plasmas, Vol. 21, Issue 9
  • DOI: 10.1063/1.4894484

Role of electron physics in the development of turbulent magnetic reconnection in collisionless plasmas
journal, April 2011

  • Daughton, W.; Roytershteyn, V.; Karimabadi, H.
  • Nature Physics, Vol. 7, Issue 7
  • DOI: 10.1038/nphys1965

Fully kinetic simulations of undriven magnetic reconnection with open boundary conditions
journal, July 2006

  • Daughton, William; Scudder, Jack; Karimabadi, Homa
  • Physics of Plasmas, Vol. 13, Issue 7
  • DOI: 10.1063/1.2218817

Particle Acceleration by Magnetic Reconnection
book, October 2014


A Magnetic Reconnection Mechanism for the Generation of Anomalous Cosmic rays
journal, January 2010


Production of Energetic Electrons during Magnetic Reconnection
journal, March 2005


Electron acceleration from contracting magnetic islands during reconnection
journal, October 2006


The Power-Law Spectra of Energetic Particles During Multi-Island Magnetic Reconnection
journal, December 2012


First-order Fermi acceleration driven by magnetic reconnection: Fermi acceleration and magnetic reconnection
journal, March 2012


Cosmic-ray viscosity
journal, August 1988

  • Earl, J. A.; Jokipii, J. R.; Morfill, G.
  • The Astrophysical Journal, Vol. 331
  • DOI: 10.1086/185242

Large-scale electron acceleration by parallel electric fields during magnetic reconnection
journal, February 2012

  • Egedal, J.; Daughton, W.; Le, A.
  • Nature Physics, Vol. 8, Issue 4
  • DOI: 10.1038/nphys2249

A review of pressure anisotropy caused by electron trapping in collisionless plasma, and its implications for magnetic reconnection
journal, June 2013

  • Egedal, Jan; Le, Ari; Daughton, William
  • Physics of Plasmas, Vol. 20, Issue 6
  • DOI: 10.1063/1.4811092

The process of electron acceleration during collisionless magnetic reconnection
journal, January 2006

  • Fu, X. R.; Lu, Q. M.; Wang, S.
  • Physics of Plasmas, Vol. 13, Issue 1
  • DOI: 10.1063/1.2164808

Formation of Hard Power Laws in the Energetic Particle Spectra Resulting from Relativistic Magnetic Reconnection
journal, October 2014


Particle Acceleration and Plasma Dynamics During Magnetic Reconnection in the Magnetically Dominated Regime
journal, June 2015


Suprathermal electron acceleration in magnetic reconnection
journal, November 2001

  • Hoshino, M.; Mukai, T.; Terasawa, T.
  • Journal of Geophysical Research: Space Physics, Vol. 106, Issue A11
  • DOI: 10.1029/2001JA900052

Particle drift, diffusion, and acceleration at shocks
journal, April 1982

  • Jokipii, J. R.
  • The Astrophysical Journal, Vol. 255
  • DOI: 10.1086/159870

The generalized diffusion-convection equation
journal, September 1990

  • Jones, Frank C.
  • The Astrophysical Journal, Vol. 361
  • DOI: 10.1086/169179

Particle Densities Within the Acceleration Region of a Solar Flare
journal, December 2013


Measurements of the Coronal Acceleration Region of a Solar Flare
journal, April 2010


Regimes of the Electron Diffusion Region in Magnetic Reconnection
journal, March 2013


A Kinetic Transport Theory for Particle Acceleration and Transport in Regions of Multiple Contracting and Reconnecting Inertial-Scale flux Ropes
journal, March 2015


NONTHERMALLY DOMINATED ELECTRON ACCELERATION DURING MAGNETIC RECONNECTION IN A LOW- β PLASMA
journal, September 2015


Particle Acceleration during Magnetic Reconnection in a Low-beta Plasma
journal, June 2017


Non-thermal processes in large solar flares
journal, January 1976


Particle energization in 3D magnetic reconnection of relativistic pair plasmas
journal, May 2011

  • Liu, Wei; Li, Hui; Yin, Lin
  • Physics of Plasmas, Vol. 18, Issue 5
  • DOI: 10.1063/1.3589304

A Quantitative Model of Energy Release and Heating by Time-dependent, Localized Reconnection in a Flare with Thermal Loop-top X-ray Source
journal, October 2010


Impact of compressibility and a guide field on Fermi acceleration during magnetic island coalescence
journal, June 2017

  • Montag, P.; Egedal, J.; Lichko, E.
  • Physics of Plasmas, Vol. 24, Issue 6
  • DOI: 10.1063/1.4985302

On the Distribution of Particle Acceleration Sites in Plasmoid-Dominated Relativistic Magnetic Reconnection
journal, December 2015

  • Nalewajko, Krzysztof; Uzdensky, Dmitri A.; Cerutti, Benoît
  • The Astrophysical Journal, Vol. 815, Issue 2
  • DOI: 10.1088/0004-637X/815/2/101

Kappa Distribution Model for hard X-Ray Coronal Sources of Solar Flares
journal, January 2013


Electron Energy Partition in the Above-The-Looptop Solar hard X-Ray Sources
journal, January 2015


Electron Acceleration by Multi-Island Coalescence
journal, April 2010


The passage of energetic charged particles through interplanetary space
journal, January 1965


Relativistic electron production during guide field magnetic reconnection
journal, January 2006


Plasma Compression in Magnetic Reconnection Regions in the Solar Corona
journal, June 2016


Cosmic Ray Streaming--II EFFECT OF PARTICLES ON ALFVEN WAVES
journal, November 1975


The Mechanisms of Electron Acceleration During Multiple x line Magnetic Reconnection with a Guide Field
journal, April 2016


Diffusive Shock Acceleration and Reconnection Acceleration Processes
journal, November 2015


Particle Acceleration via Reconnection Processes in the Supersonic Solar wind
journal, November 2014


Electron Acceleration by Cascading Reconnection in the Solar Corona. i. Magnetic Gradient and Curvature Drift Effects
journal, December 2015


Magnetic Reconnection in Astrophysical and Laboratory Plasmas
journal, September 2009


Electron Acceleration by Multi-Island Coalescence
text, January 2010


First order particle acceleration in magnetically-driven flows
text, January 2014


Plasma compression in magnetic reconnection regions in the solar corona
text, January 2016


Works referencing / citing this record:

Explosive Magnetotail Activity
journal, May 2019

  • Sitnov, Mikhail; Birn, Joachim; Ferdousi, Banafsheh
  • Space Science Reviews, Vol. 215, Issue 4
  • DOI: 10.1007/s11214-019-0599-5

Summary of the fundamental plasma physics session in the first AAPPS-DPP conference
journal, May 2019


Energy transfer and electron energization in collisionless magnetic reconnection for different guide-field intensities
journal, December 2018

  • Pucci, F.; Usami, S.; Ji, H.
  • Physics of Plasmas, Vol. 25, Issue 12
  • DOI: 10.1063/1.5050992

A computational model for exploring particle acceleration during reconnection in macroscale systems
journal, January 2019

  • Drake, J. F.; Arnold, H.; Swisdak, M.
  • Physics of Plasmas, Vol. 26, Issue 1
  • DOI: 10.1063/1.5058140

Self-consistent Energetic Particle Acceleration by Contracting and Reconnecting Small-scale Flux Ropes: The Governing Equations
journal, September 2018

  • le Roux, J. A.; Zank, G. P.; Khabarova, O. V.
  • The Astrophysical Journal, Vol. 864, Issue 2
  • DOI: 10.3847/1538-4357/aad8b3

Magnetic Reconnection Null Points as the Origin of Semirelativistic Electron Beams in a Solar Jet
journal, October 2018


Large-scale Compression Acceleration during Magnetic Reconnection in a Low- β Plasma
journal, October 2018


Plasma Energization in Colliding Magnetic Flux Ropes
journal, October 2018


Electron and Proton Heating in Transrelativistic Guide Field Reconnection
journal, February 2019

  • Rowan, Michael E.; Sironi, Lorenzo; Narayan, Ramesh
  • The Astrophysical Journal, Vol. 873, Issue 1
  • DOI: 10.3847/1538-4357/ab03d7

Particle Acceleration in Kinetic Simulations of Nonrelativistic Magnetic Reconnection with Different Ion–Electron Mass Ratios
journal, June 2019


Current Sheets, Magnetic Islands, and Associated Particle Acceleration in the Solar Wind as Observed by Ulysses near the Ecliptic Plane
journal, August 2019

  • Malandraki, Olga; Khabarova, Olga; Bruno, Roberto
  • The Astrophysical Journal, Vol. 881, Issue 2
  • DOI: 10.3847/1538-4357/ab289a

Particle Acceleration and Heating in Regions of Magnetic Flux Emergence
journal, September 2019


Formation of Power-law Electron Energy Spectra in Three-dimensional Low- β Magnetic Reconnection
journal, October 2019


Modeling Energetic Particle Acceleration and Transport in a Solar Wind Region with Contracting and Reconnecting Small-scale Flux Ropes at Earth Orbit
journal, December 2019

  • Le Roux, J. A.; Webb, G. M.; Khabarova, O. V.
  • The Astrophysical Journal, Vol. 887, Issue 1
  • DOI: 10.3847/1538-4357/ab521f

Super-efficient Electron Acceleration by an Isolated Magnetic Reconnection
journal, January 2019


Determining the Dominant Acceleration Mechanism during Relativistic Magnetic Reconnection in Large-scale Systems
journal, July 2019


Energetic Electron Acceleration in Unconfined Reconnection Jets
journal, August 2019


Electron and Proton Heating in Transrelativistic Guide Field Reconnection
text, January 2019


Explosive Magnetotail Activity
journal, May 2019

  • Sitnov, Mikhail; Birn, Joachim; Ferdousi, Banafsheh
  • Space Science Reviews, Vol. 215, Issue 4
  • DOI: 10.1007/s11214-019-0599-5