Studying the collimation of outflows in radially converging plasmas from a 3D printed load

We present new results as a continuation of a scaled laboratory study on the stability and collimation of astrophysical plasma outflows using the COBRA pulsed power driver at Cornell University [1]. In this new experimental campaign, we use the simplest version of the load hardware design in which the axial magnetic field component has been removed. Additionally, the spacings between the initial and return current paths have been increased in order to protect from parasitic current arcing.  Our goal of this campaign is to scan across the time-evolution of the plasma’s structure with laser interferometry and extreme ultraviolet (XUV) imaging in order to find any indication that collimated outflows are present in our simplest 3D printed load design. We present evidence of an overdensity at the center of our converging flows from top-down and side-on viewpoints of the XUV images, as well as evidence of streams emerging from the plasma in the interferometry data. We also discuss the introduction of higher-Z wires into two of the six current paths.

1. H. R. Hasson et al. “Design of a 3-D Printed Experimental Platform for Studying the Formation and Magnetization of Turbulent Plasma Jets”. IEEE Transactions on Plasma Science (2020).