Dartmouth Events

Abstract: Laboratory experiments—and the models they inspire—provide powerful tools for exploring the plasma universe. In this talk, I begin with a laboratory investigation of solar flare generation and the modeling of astrophysical braided helical structures, such as those observed in astrophysical jets. I then extend the discussion to a broader range of astrophysical processes reproduced in laboratory settings using diverse experimental platforms.

I will present observations from a laboratory experiment that simulates solar coronal loop physics. Transient, localized 7.6-keV X-ray bursts and a several-kilovolt voltage spike are observed to be associated with the breaking of braided magnetic flux ropes containing 2 eV plasma. These spikes occur when the braid strand radius is choked down to be at the kinetic scale by either MHD kink or magnetic Rayleigh–Taylor instabilities. The observed sequence reveals an MHD to non-MHD cross-scale coupling that is likely responsible for generating solar energetic particles and X-ray bursts.

Motivated by these results, we propose a model of interacting flux ropes that captures the formation of braided helical structures. This framework may help explain the frequently observed braided morphologies in solar coronal loops, astrophysical jets, and double-helix nebulae. To further investigate this physics, a dedicated Z-pinch experimental campaign will be conducted this summer at Sandia.

Finally, I will highlight a range of laboratory platforms that bring key astrophysical processes into the lab, including angular momentum transport in rotating plasmas relevant to planet formation, as well as laser-driven studies of magnetic reconnection and jet formation. These examples demonstrate how carefully designed experiments can capture essential physics from space in a controlled setting, pointing toward a unified approach to understanding the plasma universe and inspiring future experimental directions.

Hosted by Assistant Professor Muni Zhou

Zoom link: https://dartmouth.zoom.us/j/99960465228