The small scale ejection phenomena, plasmoids, are believed to play an important role in the coronal dynamics and mass balance. First direct observations of small (sub-arcsec) plasmoids propagating in the corona (Koutchmy et al. 1994, Astron. AStrophys., 281, 249) revealed details of dynamic behavior of plasmoid and lead authors to the plausible model of plasmoid as a toroidal vortex. Many questions regarding the interaction of the a cool magnetized plasmoid with surrounding hot plasma remain unclear. These processes can be simulated in the laboratory experiment using an accelerated spheromak-like compact toroid (SCT) injected into a tokamak magnetized target region. The UC Davis Compact Toroid accelerator (CTIX) is designed to study the formation and acceleration of a compact toroid under repetitive operation, and to diagnose the interaction and thermalization of the plasmoid as it is injected into a target region. We present results of the experiment with the parameters of the plasmoid and target plasma, scalable to solar parameters. The different range of parameters and geometry of the external magnetic field were used to simulate the various conditions of the propagation of the compact toroid in the target chamber. We show that in most cases the field reversal in the shell between the compact toroid and ambient field occurs, suggesting a strong coupling between the toroid and the ambient field that imay eventually leads to the shock formation. We estimate the particle inventory balance depending on the SCT injection rate and geometry. Using scalability criteria, we present quantitative comparison between the dynamics of the compact toroid and the observed properties of the coronal plasmoid. This work is jointly supported by NSF and DOE.
AGU Spring Meeting Abstracts
- Pub Date:
- May 2002
- 7509 Corona;
- 7599 General or miscellaneous