Progress on the Development of Low Pressure High Density Plasmas on the Helicon Plasma Experiment (HPX)

The small Helicon Plasma Experiment (HPX) at the Coast Guard Academy Plasma Lab (CGAPL), continues to progress toward utilizing the reputed high densities (10¹³ cm-³ and higher) at low pressure (.01 T) [1] of helicons, for eventual high temperature and density diagnostic development in future laboratory investigations. HPX is designed to create repeatedly stable plasmas ( 20-30 ns) induced by an RF frequency in the 10 to 70 MHz range. HPX has constructed a protected Langmuir probe where raw data will be collected, compared to the RF compensated probe and used to measure the plasma's density, temperature, and behavior during experiments. Our 2.5 J YAG laser Thomson Scattering system backed by a 32-channel Data Acquisition (DAQ) system is capable 12 bits of sampling precision at 2 MS/s for HPX plasma property investigations are being integrated into the existing diagnostics and control architecture. Progress on the construction of the RF coupling system, Helicon Mode development, and magnetic coils, along with observations from the Thomson Scattering, particle, and electromagnetic scattering diagnostics will be reported.

Supported by U.S. DEPS Grant [HEL-JTO] PRWJFY17.