HR: 0800h
AN: SM51B-06    [Abstracts]
TI: Dynamics of Magnetic Flux Ropes in a Laboratory Plasma
AU: * Lawrence, E E
EM: lawrence@physics.ucla.edu
AF: University of California at Los Angeles, 1000 Veteran Ave Suite 15-70, Los Angeles, CA 90036, United States
AU: Gekelman, W
EM: gekelman@physics.ucla.edu
AF: University of California at Los Angeles, 1000 Veteran Ave Suite 15-70, Los Angeles, CA 90036, United States
AB: The behavior and interaction of magnetic flux ropes has long been a topic of interest to solar and space plasma physicists. (Gekelman, et al. IEEE Trans. Plasma Sci. 20, 614. Furno, et al. Phys. Plasmas 12, 055702.) Very few laboratory experiments have been performed as it is necessary to have a relatively collisionless plasma and currents with significant self-generated fields. Movable lanthanum hexaboride (LaB₆) cathodes have been developed to study the 3D dynamics of flux ropes in the Large Plasma Device (LaPD). The background plasma (n ~ 2 × 10¹² cm ^-3, d ~ 60 cm, L ~ 18 m, and τ_{rep= 1 s) is produced with a DC discharge using a pulsed barium oxide-coated cathode. The two or more current channels are created by biasing the LaB6 disks with respect to a grid anode at the opposite end of the chamber. They are emitted parallel to each other and the guide field. J × B forces cause the currents to move across the field and interact. Each 2.5 cm LaB6 disk can produce current densities of 5-10 A/cm², and can be positioned freely within a transverse plane of the cylindrical LaPD. We plan to make detailed volumetric measurements of the magnetic fields and flows generated by the current channels. Diagnostics include Ḃ, Langmuir, and Mach probes, and laser induced fluorescence. Research is supported by the Department of Energy (grant DE-FG02-03ER54717) and conducted at the Basic Plasma Science Facility at UCLA.}
DE: 7831 Laboratory studies and experimental techniques
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly