Bellan, P. M. and Hansen, J. F. (1998) Laboratory simulations of solar prominence eruptions. Physics of Plasmas, 5 (5). pp. 1991-2000. ISSN 1070-664X http://resolver.caltech.edu/CaltechAUTHORS:BELpop98a
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:BELpop98a
Spheromak technology is exploited to create laboratory simulations of solar prominence eruptions. It is found that the initial simulated prominences are arched, but then bifurcate into twisted secondary structures which appear to follow fringing field lines. A simple model explains many of these topological features in terms of the trajectories of field lines associated with relaxed states, i.e., states satisfying [del] × B = lambda B. This model indicates that the field line concept is more fundamental than the flux tube concept because a field line can always be defined by specifying a starting point whereas attempting to define a flux tube by specifying a starting cross section typically works only if lambda is small. The model also shows that, at least for plasma evolving through a sequence of force-free states, the oft-used line-tying concept is in error. Contrary to the predictions of line-tying, direct integration of field line trajectories shows explicitly that when lambda is varied, both ends of field lines intersecting a flux-conserving plane do not remain anchored to fixed points in that plane. Finally, a simple explanation is provided for the S-shaped magnetic structures often seen on the sun; the S shape is shown to be an automatic consequence of field line arching and the parallelism between magnetic field and current density for force-free states.
|Additional Information:||©1998 American Institute of Physics. (Received 12 November 1997; accepted 13 January 1998) We wish to thank F. C. Cosso for assistance with vacuum and electronics and J. Yee for assistance with operation of the high-speed camera. This work was supported by the National Science Foundation and the United States Department of Energy. P. M. Bellan, Invited speaker. An earlier version was presented -- Paper eMopI2-2 Bull. Am. Phys. Soc. 42, 1871 (1997).|
|Subject Keywords:||PLASMA SIMULATION; SOLAR PROMINENCES; SPHEROMAK DEVICES; PLASMA CONFINEMENT|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Archive Administrator|
|Deposited On:||22 Feb 2006|
|Last Modified:||26 Dec 2012 08:46|
Repository Staff Only: item control page