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Title: Role of electric fields in the MHD evolution of the kink instability

Abstract

Here, the discovery of electrostatic fields playing a crucial role in establishing plasma motion in the flux conversion and dynamo processes in reversed field pinches is revisited. In order to further elucidate the role of the electrostatic fields, a flux rope configuration susceptible to the kink instability is numerically studied with anMHDcode. Simulated nonlinear evolution of the kink instability is found to confirm the crucial role of the electrostatic fields. Anew insight is gained on the special function of the electrostatic fields: they lead the plasma towards the reconnection site at the mode resonant surface. Without this step the plasma column could not relax to its nonlinear state, since no other agent is present to perform this role. While the inductive field generated directly by the kink instability is the dominant flow driver, the electrostatic field is found to allow the motion in the vicinity of the reconnection region.

Authors:
 [1];  [2]
  1. Katholieke Universiteit Leuven, Leuven (Belguim)
  2. Istituto Nazionale di Astrofisica, Napoli (Italy)
Publication Date:
Research Org.:
Katholieke Universiteit Leuven, Leuven (Belguim)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24); USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1356079
Alternate Identifier(s):
OSTI ID: 1358366
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
New Journal of Physics
Additional Journal Information:
Journal Volume: 19; Journal Issue: 2; Journal ID: ISSN 1367-2630
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; MHD; kink instability; magnetic reconnection; self-organization; flux rope; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Lapenta, Giovanni, and Skender, Marina. Role of electric fields in the MHD evolution of the kink instability. United States: N. p., 2017. Web. doi:10.1088/1367-2630/aa5de9.
Lapenta, Giovanni, & Skender, Marina. Role of electric fields in the MHD evolution of the kink instability. United States. doi:10.1088/1367-2630/aa5de9.
Lapenta, Giovanni, and Skender, Marina. Fri . "Role of electric fields in the MHD evolution of the kink instability". United States. doi:10.1088/1367-2630/aa5de9. https://www.osti.gov/servlets/purl/1356079.
@article{osti_1356079,
title = {Role of electric fields in the MHD evolution of the kink instability},
author = {Lapenta, Giovanni and Skender, Marina},
abstractNote = {Here, the discovery of electrostatic fields playing a crucial role in establishing plasma motion in the flux conversion and dynamo processes in reversed field pinches is revisited. In order to further elucidate the role of the electrostatic fields, a flux rope configuration susceptible to the kink instability is numerically studied with anMHDcode. Simulated nonlinear evolution of the kink instability is found to confirm the crucial role of the electrostatic fields. Anew insight is gained on the special function of the electrostatic fields: they lead the plasma towards the reconnection site at the mode resonant surface. Without this step the plasma column could not relax to its nonlinear state, since no other agent is present to perform this role. While the inductive field generated directly by the kink instability is the dominant flow driver, the electrostatic field is found to allow the motion in the vicinity of the reconnection region.},
doi = {10.1088/1367-2630/aa5de9},
journal = {New Journal of Physics},
number = 2,
volume = 19,
place = {United States},
year = {Fri Feb 17 00:00:00 EST 2017},
month = {Fri Feb 17 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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  • The discovery (Bonfiglio et al 2005 Phys. Rev. Lett. 94 145001) of electrostatic fields playing a crucial role in establishing plasma motion in the flux conversion and dynamo processes in reversed field pinches is revisited. In order to further elucidate the role of the electrostatic fields, a flux rope configuration susceptible to the kink instability is numerically studied with anMHDcode. Simulated nonlinear evolution of the kink instability is found to confirm the crucial role of the electrostatic fields. Anew insight is gained on the special function of the electrostatic fields: they lead the plasma towards the reconnection site at themore » mode resonant surface. Without this step the plasma column could not relax to its nonlinear state, since no other agent is present to perform this role. While the inductive field generated directly by the kink instability is the dominant flow driver, the electrostatic field is found to allow the motion in the vicinity of the reconnection region.« less
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