Reconnection Spreading Between Non-Parallel Flux Ropes in 3D Simulations of the WVU PHASMA Experiment

Authors: Regis John (West Virginia University), Paul Cassak (West Virginia University), Subash Adhikari (West Virginia University), Gustavo Elias Bartolo (West Virginia University), Sonu Yadav (West Virginia University), Earl Scime (West Virginia University)

Magnetic flux ropes are columns of plasma with axial and azimuthal magnetic fields and are commonly observed in the solar corona. The West Virginia University PHAse Space MApping (PHASMA) experiment generates flux ropes in the lab to study their dynamics and how they reconnect. Two flux ropes are created using pulsed plasma guns in a strong background magnetic field. The flux ropes are fixed in space at one end (the plasma gun end) and the other end of the ropes terminates on a conical anode, which introduces a small degree of tilt between the two flux ropes. In the experiment, the flux ropes rotate around each other and move towards and away from each other throughout the discharge. Reconnection occurs in the region between the ropes during the “pull” and “push” phases of the relative motion of the ropes. The ropes fully merge if the axial magnetic field is less than ten times the reconnecting field (150 G). Here, we present 3D electron-magnetohydrodynamics (EMHD) simulation results using the F3D code of reconnecting flux ropes tilted at an angle. We find reconnection spreads in a zipper-like fashion with dynamics depending on the axial magnetic field strength. We perform a parametric study as a function of the axial magnetic field and compare it to the laboratory observations.