Authors: Joshua Morgan (Caltech), Paul Bellan (Caltech)

The Caltech MHD Plasma Jet experiment generates a relatively low temperature plasma of approximately 2eV and density of approximately 10^21m-3, and yet has been observed to emit X-rays with energies as high as 13KeV. How a modest temperature plasma generates electrons energetic enough to produce these X-rays is an open question. An optical diagnostic tool was constructed which allows monochromatic images at two different optical wavelengths to be captured side by side on the same frame. The dynamics of a hydrogen plasma jet are investigated using this tool, with specific focus on the spatiotemporal evolution of temperature and density. The temperature of neutral hydrogen atoms embedded in the jet is mapped using a two-point Saha-Boltzmann line regression on the Hα and Hβ spectral lines, which are captured via broadband optical filters. The density is mapped by capturing Stark broadening of the Hβ spectral line using ultra-narrowband filters at wavelengths in the near and far wings of Hβ. Specific attention is given to a hydrogen plasma undergoing the kink instability and a secondary Rayleigh-Taylor instability (RTI), for which temperature and density maps are generated. A preliminary goal is to measure the correlation between local density reduction, temperature fluctuation, and overall dimming of the plasma in the region of the RTI.  This measurement is expected to provide information relevant to how a low temperature plasma can generate electrons greatly exceeding the average thermal velocity.