Experimental study of magnetic bubble expansion as a model for extragalactic radio lobes

University Of New Mexico, Albuquerque NM

Investigators

Abstract

0613577 Lynn This project will conduct laboratory experiments and coordinated numerical modeling to help address outstanding plasma physics issues related to how magnetic energy and helicity carried by extra-galactic jets reach quasi-equilibrium with the intergalactic medium, forming gigantic 'radio lobes' which are thought to be gigantic relaxed plasmas. The experiments will study the relaxation of a magnetized plasma bubble as it expands into and reaches equilibrium with a lower pressure background plasma. The primary scientific objectives are to characterize the underlying nonlinear plasma physics of the bubble relaxation, including magnetic flux conversion, ion and electron heating, and angular momentum evolution/transport. These nonlinear plasma physics issues cannot at present be resolved from numerical computation or astronomical observations alone. The experimental results will provide insights into the bubble expansion/relaxation process and the needed data for validating numerical computations being carried out in this field. Experimental parameters will be adjusted so that important dimensionless parameters relating to magnetic flux, electric current, helicity injection rate (and duration), and total injected helicity are relevant for the astrophysical context.