title: Blackbody emission from laser breakdown in high-pressure gases.
abstract: Laser induced breakdown of pressurized gases is used to generate plasmas under conditions where the atomic density and temperature are similar to those found in sonoluminescing bubbles. Calibrated streak spectroscopy reveals that a blackbody persists well after the exciting femtosecond laser pulse has turned off. Deviation from Saha's equation of state and an accompanying large reduction in ionization potential are observed at unexpectedly low atomic densities-in parallel with sonoluminescence. In laser breakdown, energy input proceeds via excitation of electrons whereas in sonoluminescence it is initiated via the atoms. The similar responses indicate that these systems are revealing the thermodynamics and transport of a strongly coupled plasma.
authors.affiliation: Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
authors.forename: A
authors.initials: A
authors.lastname: Bataller
authors.affiliation: Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
authors.forename: G R
authors.initials: GR
authors.lastname: Plateau
authors.affiliation: Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
authors.forename: B
authors.initials: B
authors.lastname: Kappus
authors.affiliation: Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
authors.forename: S
authors.initials: S
authors.lastname: Putterman