Evolution of Ultracold, Neutral Plasmas

We present the first large-scale simulations of an ultracold, neutral plasma, produced by photoionization of laser-cooled xenon atoms, from creation to initial expansion, using classical molecular dynamics methods with open boundary conditions. We reproduce many of the experimental findings such as the trapping efficiency of electrons with increased ion number, a minimum electron temperature achieved on approach to the photoionization threshold, and recombination into Rydberg states of anomalously-low principal quantum number. In addition, many of these effects establish themselves very early in the plasma evolution ($\sim$ ns) before present experimental observations begin.Comment: 4 pages, 3 figures, submitted to PR

Characterization of afterglow kinetics at atmospheric pressures by emission spectroscopy: II. Reactions of neon ions with Xe

International audienceThe afterglow of a 1 kA, 10 ns duration discharge in neon at 1.1-4.0 bar pressure containing up to 30 mbar of reactant admixture Xe was studied by time-resolved emission spectroscopy. Destruction frequencies of neon ions have been determined experimentally both from the selectively excited fluorescence of N2+ and from the radiation of excited xenon atoms. These data confirm the existence of a termolecular charge-transfer reaction of Ne2+ with Xe, the corresponding rate coefficient being (2.6+-0.3)10-30 cm6s-1. Also the fact that vibrationally excited Ne2+ ions play an important role was confirmed. A persistent source of ionization at late afterglow times has been studied in some detail and was interpreted in terms of collisions between xenon atoms in their first excited states 3P2 and 3P1. The decay processes of these atoms were identified as partially trapped resonance radiation and three-body conversion to Xe2 dimer

Experimental study on X-ray emission of nanometric argon clusters irradiated with intense laser pulses

no abstrac

Reactions of He(2 3 S ) with argon at atmospheric pressures

International audienc

Experimental study of K-shell X-ray emission from argon clusters irradiated by an ultra-intense laser pulse

no abstrac

Experimental study of K-shell X-ray emission from argon clusters irradiated by an ultra-intense laser pulse

International audienceno abstrac

Multi-keV picosecond x-ray source development from ultra-intense kHz laser-cluster interaction

no abstrac