NDLI: Dynamics of Laser-Plasma Expansion Across Strong Magnetic Field

Content Provider	IEEE Xplore Digital Library
Author	Presura, R. Ivanov, V.V. Sentoku, Y. Esaulov, A. Sotnikov, V.I. Neff, S. Plechaty, C. Wright, S. Laca, P.J. Haboub, A. Morozov, A. Bakeman, M. Gaillard, S. Leblanc, P. Royle, R. Andersen, J. Cowan, T.E.
Copyright Year	2007
Description	Author affiliation: Nevada Univ., Reno (Presura, R.; Ivanov, V.V.; Sentoku, Y.; Esaulov, A.; Sotnikov, V.I.; Neff, S.; Plechaty, C.; Wright, S.; Laca, P.J.; Haboub, A.; Morozov, A.; Bakeman, M.; Gaillard, S.; Leblanc, P.; Royle, R.; Andersen, J.; Cowan, T.E.)
Abstract	Summary form only given. Explosive plasma expansion in an external magnetic field occurs in a variety of space and astrophysical events that include supernova explosions in the interstellar magnetic field and the interaction of solar coronal mass ejections with planetary magnetospheres. We investigated in the laboratory the interaction of plasma winds with magnetic obstacles for various degrees of ion magnetization. In these experiments, an azimuthal magnetic field with flux density up to 30 T was generated by high current discharges of the pulsed-povver generator Zebra (0.6 MA maximum current with 200 ns rise time) in a reusable short-circuit load. The plasma wind was created by ablation of a solid $CH_{2}$ target with the pulsed laser Tomcat (1 mum wavelength). Laser pulses 6 ns long with energy up to 5 J and irradiance up to $10^{14}$ $W/cm^{2}$ were used to investigate the large Larmor radius regime. The regime in which ions are magnetized was studied with short laser pulses (4 J in 5 ps, with irradiance up to $10^{16}$ $W/cm^{2}).$ In both experiments the plasma and magnetic field were characterized with multi-frame laser shadow and schlieren imaging and magnetic probes, respectively. Without the magnetic field, the laser diagnostics show a plasma plume expanding quasi-spherically. When a magnetic field is present, it decelerates the plasma flow and a steep density gradient forms at the interaction front. The boundary forms in regions where the density would be too low to observe with laser diagnostics without the magnetic field. When observing the plasma evolution over times much longer than the inverse ion gyrofrequency, the density gradient decreases at the plasma front in the direction normal to the target and the plasma flows beyond the initial boundary. In the transverse direction, the boundary becomes unstable. Most likely, this is a result of the electrons being trapped in the magnetic field along the interface. As a result they decelerate the ions producing a region of velocity shear across the interface. This configuration is favorable for the onset of instabilities. Three-dimensional ideal magnetohydrodynamic (MHD) modeling describes well the formation of a diamagnetic cavity, the dynamics of the plasma plume during the interaction with the magnetic field, and the onset of instabilities at the plasma-field interface. Two dimensional particle-in-cell modeling describes well details of the plasma-field interaction at the boundary and the plasma penetration across the field beyond the limit predicted by MHD.
Starting Page	769
Ending Page	769
File Size	58170
Page Count	1
File Format	PDF
ISBN	9781424409150
ISSN	07309244
DOI	10.1109/PPPS.2007.4346075
Language	English
Publisher	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Publisher Date	2007-06-17
Publisher Place	USA
Access Restriction	Subscribed
Rights Holder	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subject Keyword	Magnetic fields Plasma density Plasma diagnostics Magnetic flux Magnetosphere Optical pulses Magnetohydrodynamics Optical pulse generation Solar power generation Laser ablation
Content Type	Text
Resource Type	Article
Subject	Atomic and Molecular Physics, and Optics Condensed Matter Physics Electrical and Electronic Engineering

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in