Collisionless kinetic theory of oblique tearing instabilities
The linear dispersion relation for collisionless kinetic tearing instabilities is calculated for the Harris equilibrium. In contrast to the conventional 2D geometry, which considers only modes at the center of the current sheet, modes can span the current sheet in 3D. Modes at each resonant surface have a unique angle with respect to the guide field direction. Both kinetic simulations and numerical eigenmode solutions of the linearized VlasovMaxwell equations have recently revealed that standard analytic theories vastly overestimate the growth rate of oblique modes. In this paper, we find that this stabilization is associated with the densitygradientdriven diamagnetic drift. The analytic theories miss this drift stabilization because the inner tearing layer broadens at oblique angles sufficiently far that the assumption of scale separation between the inner and outer regions of boundarylayer theory breaks down. The dispersion relation obtained by numerically solving a single second order differential equation is found to approximately capture the drift stabilization predicted by solutions of the full integrodifferential eigenvalue problem. Finally, a simple analytic estimate for the stability criterion is provided.
 Authors:

^{[1]};
^{[2]};
^{[3]}
 Univ. of Iowa, Iowa City, IA (United States). Dept. of Physics and Astronomy
 Princeton Univ., NJ (United States). Dept. of Astrophysical Sciences; Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Report Number(s):
 LAUR1821045
Journal ID: ISSN 1070664X; TRN: US1802606
 Grant/Contract Number:
 SC0016159; AGS0962698; AC5206NA25396
 Type:
 Accepted Manuscript
 Journal Name:
 Physics of Plasmas
 Additional Journal Information:
 Journal Volume: 25; Journal Issue: 2; Journal ID: ISSN 1070664X
 Publisher:
 American Institute of Physics (AIP)
 Research Org:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Univ. of Iowa, Iowa City, IA (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC24); National Science Foundation (NSF)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; kinetic theory; dispersion; magnetic reconnection; ionospheric physics; plasma dynamics; magnetospheric dynamics; physical optics; plasma instabilities; plasma interactions; flow boundary effects
 OSTI Identifier:
 1429052
 Alternate Identifier(s):
 OSTI ID: 1421302; OSTI ID: 1438147
Baalrud, S. D., Bhattacharjee, A., and Daughton, W.. Collisionless kinetic theory of oblique tearing instabilities. United States: N. p.,
Web. doi:10.1063/1.5020777.
Baalrud, S. D., Bhattacharjee, A., & Daughton, W.. Collisionless kinetic theory of oblique tearing instabilities. United States. doi:10.1063/1.5020777.
Baalrud, S. D., Bhattacharjee, A., and Daughton, W.. 2018.
"Collisionless kinetic theory of oblique tearing instabilities". United States.
doi:10.1063/1.5020777.
@article{osti_1429052,
title = {Collisionless kinetic theory of oblique tearing instabilities},
author = {Baalrud, S. D. and Bhattacharjee, A. and Daughton, W.},
abstractNote = {The linear dispersion relation for collisionless kinetic tearing instabilities is calculated for the Harris equilibrium. In contrast to the conventional 2D geometry, which considers only modes at the center of the current sheet, modes can span the current sheet in 3D. Modes at each resonant surface have a unique angle with respect to the guide field direction. Both kinetic simulations and numerical eigenmode solutions of the linearized VlasovMaxwell equations have recently revealed that standard analytic theories vastly overestimate the growth rate of oblique modes. In this paper, we find that this stabilization is associated with the densitygradientdriven diamagnetic drift. The analytic theories miss this drift stabilization because the inner tearing layer broadens at oblique angles sufficiently far that the assumption of scale separation between the inner and outer regions of boundarylayer theory breaks down. The dispersion relation obtained by numerically solving a single second order differential equation is found to approximately capture the drift stabilization predicted by solutions of the full integrodifferential eigenvalue problem. Finally, a simple analytic estimate for the stability criterion is provided.},
doi = {10.1063/1.5020777},
journal = {Physics of Plasmas},
number = 2,
volume = 25,
place = {United States},
year = {2018},
month = {2}
}