Line Opacity in X-pinch Plasmas

POSTER

Abstract

Self-absorption features have been observed during the compression phase of hybrid X-pinch (HXP) plasmas1. Previous spectroscopic studies of X-pinches have estimated line opacity from time‑integrated strong/weak line ratios2 . Current studies are exploring line opacity during the compression phase through time resolved strong and weak line ratios. The time- resolved ratios are used to track opacity throughout compression, inverting them with an escape factor model to yield a column density history Ner(t) and the corresponding monochromatic opacity kappa_lambda(t) of the hotspot. These experiments are performed on the XP pulsed power generator with the 450-kA peak current and a rise time of 60 ns (10 to 90%).

*We would also like to give thanks to Todd Blanchard, Dan Hawkes, William Potter, and Harry Wilhelm for their technical support. This research is supported by NNSA funding under the HEDLP Joint Program with DOE FES contract #DE-NA0004027. Formerly funded by DOE FES grant number DE-SC0018088. Partially supported by Center for Magnetic Acceleration, Compression, and Heating (MACH), part of the U.S. DOE-NNSA Stewardship Science Academic Alliances Program under Cooperative Agreement DE-NA0004148.

Publication:
[1] A. T. Elshafiey, N. G. Chalmers, and D. A. Hammer, Micropinch formation dynamics in X pinches, Phys. Rev. E 110, (2024).
[2] S. A. Pikuz, D. A. Hammer, D. H. Kalantar, A. Ya. Faenov, and I. Yu. Skobelev, Phys. Rev. A 49, 3450 (1994). https://doi.org/10.1103/PhysRevA.49.3450

Presenters

  • Nathaniel Grant Chalmers

    • Cornell University

Authors

  • Nathaniel Grant Chalmers

    • Cornell University

  • David A Hammer

    • Cornell University