ENERGY FLOW IN DENSE OFF-EQUILIBRIUM PLASMAS Submitted by Seth Putterman; January 7, 2013 We have taken a movie of the transport of energy across a dense plasma! The goal is to generate and validate the kinetic theory of a dense plasma. 1 2 3 4 5 6 7 8 Frames from a movie of the propagation of an energy pulse across a dense plasma. Free charge density = 1021/cc ; diameter = 100.µm; time between frames = 10ns. Prof. K. Weninger; Dr B. Kappus

Experiment 2: Calorimetry of a Dense Plasma : shows that the Ionization potential is reduced by 85% ! Apparatus [rt] for generating A dense plasma in a spherical imploding gas bubble (40,000. implosions/s). We use xenon surrounded by sulfuric acid because of its low vapor pressure. Photo of bubble at max radius [red-left] and light emission [blue] from the dense plasma. Mie scattering over one Implosion cycle [left] with blowup near minimum radius [rt]. Energy balance based upon a precision measurement of the radius of an imploding bubble in sulfuric acid yields the energy residing in the dense plasma formed inside the collapsed bubble. A lower limit on the plasma density is determined by its 8,000K blackbody spectrum which places a lower bound of 1021/cc on the free charge. Note that the minimum radius matches the Blackbody’s spectral radius. Bataller-Kappus

Experiment 3: Diagram of Apparatus to Measure Response of Dense Plasma to Different Wavelengths of Light. The goal is to determine the collision time/kinetics of a dense plasma. Xenon in Water Bataller-Kappus

Measurement of both Mie scattering [red] and light emission [black] from a xenon gas bubble that implodes to about a one micron diameter where it forms a dense plasma – at time ‘0’ on the ‘x’ Axis. Light emission is due to two effects Thermal process in the dense plasma [lower band] Absorption and emission of a 3ns YAG pulse that hits the bubble during the 1ns lifetime of the plasma. Our measurements find that 532nm always interacts with the plasma whereas for 1064nm there is a threshold. See gap at PMT ordinate 101. While one is tempted to ascribe this behavior to the plasma frequency our theory suggests that the short collision time is in fact the key consideration.

{For neon we have a achieved a density of 1022/cc} Experiment 4: We have created a dense hydrogen plasma with a density > 1021/cc {For neon we have a achieved a density of 1022/cc} We have used a shake tube vibrating at 40Hz for this experiment. 40Hz apparatus with Xe The density of the plasma is diagnosed by its size and opacity as indicated by its blackbody Spectrum. Kappus- Weninger