Exploring extreme magnetization phenomena in directly driven imploding cylindrical targets
File(s)Walsh_2022_Plasma_Phys._Control._Fusion_64_025007.pdf (20.16 MB)
Published version
Author(s)
Type
Journal Article
Abstract
This paper uses extended-magnetohydrodynamics (MHD) simulations to explore an extreme magnetized plasma regime realizable by cylindrical implosions on the OMEGA laser facility. This regime is characterized by highly compressed magnetic fields (greater than 10 kT across the fuel), which contain a significant proportion of the implosion energy and induce large electrical currents in the plasma. Parameters governing the different magnetization processes such as Ohmic dissipation and suppression of instabilities by magnetic tension are presented, allowing for optimization of experiments to study specific phenomena. For instance, a dopant added to the target gas-fill can enhance magnetic flux compression while enabling spectroscopic diagnosis of the imploding core. In particular, the use of Ar K-shell spectroscopy is investigated by performing detailed non-LTE atomic kinetics and radiative transfer calculations on the MHD data. Direct measurement of the core electron density and temperature would be possible, allowing for both the impact of magnetization on the final temperature and thermal pressure to be obtained. By assuming the magnetic field is frozen into the plasma motion, which is shown to be a good approximation for highly magnetized implosions, spectroscopic diagnosis could be used to estimate which magnetization processes are ruling the implosion dynamics; for example, a relation is given for inferring whether thermally driven or current-driven transport is dominating.
Date Issued
2022-02-01
Date Acceptance
2021-12-01
Citation
Plasma Physics and Controlled Fusion, 2022, 64 (2), pp.1-19
ISSN
0741-3335
Publisher
IOP Publishing
Start Page
1
End Page
19
Journal / Book Title
Plasma Physics and Controlled Fusion
Volume
64
Issue
2
Copyright Statement
© 2022 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Sponsor
AWE Plc
Lawrence Livermore National Laboratory
The Royal Society
Royal Society
The Royal Society
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000741709400001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
30469588
B640100
UF120135
RGF\EA\180240
Subjects
Science & Technology
Physical Sciences
Physics, Fluids & Plasmas
Physics
magnetized HEDP
ICF
magnetized plasmas
magneto-inertial fusion
magnetohydrodynamics
extended-MHD
magnetic fields
SIMULATIONS
DYNAMICS
IONS
Publication Status
Published
OA Location
https://iopscience.iop.org/article/10.1088/1361-6587/ac3f25
Article Number
ARTN 025007
Date Publish Online
2022-01-12