Interactions between two magnetized plasma pressure filaments: Drift-Alfvén modes and transport

In this work we investigate interaction and cross-field transport between plasma filaments. The work is conducted at a linear magnetized device (LAPD, UCLA) and the temperature filaments are generated by CeB₆ crystal cathodes injecting electrons into the afterglow plasma. Transverse data planes provide spatial resolution of the filament shape and cross-field mode structure, and Langmuir sweeps provide maps of temperature and density. Temperature gradients on the exterior of the filaments drive Drift-Alfvén modes and cross-field (E×B) transport. Bringing the filaments within a few collisionless electron skin depths leads to inter-filament coupling and the formation of a symmetry-breaking convective tail on the bottom filament. Drift- Alfvén mode coupling between filaments is quantified through 2-point coherence, showing moderate but not full coupling between filaments. When the filaments are brought closer, they merge into a larger central filament and wrapped tail with a complex mode structure – when further apart, small to no tail formation occurs and the cross-filament mode coherence disappears.