Emergence of Kinetic Behavior in Streaming Ultracold Neutral Plasmas

Abstract

We create streaming ultracold neutral plasmas by tailoring the photoionizing laser beam that creates the plasma. By varying the electron temperature, we control the relative velocity of the streaming populations, and, in conjunction with variation of the plasma density, this controls the ion collisionality of the colliding streams. Laser-induced fluorescence is used to map the spatially resolved density and velocity distribution function for the ions. We identify the lack of local thermal equilibrium and distinct populations of interpenetrating, counter-streaming ions as signatures of kinetic behavior. Experimental data is compared with results from a one-dimensional, two-fluid numerical simulation.

8 pages, 6 figures

References in corpus (4)

• Molecular Dynamics Simulations of Temperature Equilibration in Dense Hydrogen
• Experimental Realization of an Exact Solution to the Vlasov Equations for an Expanding Plasma
• Electron Temperature Evolution in Expanding Ultracold Neutral Plasmas
• Collisional and Radiative Processes in Optically Thin Plasmas

Cited by in corpus (1)

• Expansion of Ultracold Neutral Plasmas with Exponentially Decaying Density Distributions