Line-Integrated Electron Density Measurements of Plasma Liner in PLX Using Multi-Chord Heterodyne Laser Interferometry

In this experiment, a novel method of multi-chord heterodyne laser interferometry has been used to take spatiotemporal line-integrated electron density measurements of the plasma within the Plasma Liner Experiment (PLX) at Los Alamos National Laboratory (LANL). PLX is a testbed for magneto-inertial fusion that creates fusion by creating a magnetized hydrogen target plasma and then compressing it with a heavy, fast-moving plasma shell (plasma liner) assembled from supersonic plasma jets. On PLX there are 4 target guns that create a magnetized hydrogen plasma and 32 liner guns that create a uniform Argon plasma liner for compression of the target. Laser interferometry on PLX is the diagnostic used to determine plasma liner electron density. The laser used is a 561 nm diode-pumped solid state (DPSS) laser with a power of 320 mW. The laser interferometry setup uses five chord beams and a reference beam in order to measure electron density at five different spatial locations radially within the plasma liner. Line-integrated electron density measurements at the center of the liner are recorded to be approximately 1.5*10¹⁸ cm^-2.