Secondary shock formation in xenon-nitrogen mixtures

Journal Article · Wed Nov 15 04:00:00 EST 2006 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2359283· OSTI ID:20860350

Hansen, J F; Edwards, M J; Froula, D H; Edens, A D; Gregori, G; Ditmire, T ^[1]

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1. Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

The expansion of shock waves has been studied in mediums with different opacities and heat capacities, varied in systematic ways by mixing xenon with nitrogen keeping the mass density constant. An initial shock is generated through the brief (5 ns) deposition of laser energy (5 J) on the tip of a pin surrounded by the xenon-nitrogen mixture. The initial shock is spherical, radiative, with a high Mach number, and it sends a supersonic radiatively driven heat wave far ahead of itself. The heat wave rapidly slows to a transonic regime and when its Mach number drops to {approx}2 with respect to the downstream plasma, the heat wave becomes of the ablative type, driving a second shock ahead of itself to satisfy mass and momentum conservation in the heat wave reference frame. The details of this sequence of events depend, among other things, on the opacity and heat capacity of the surrounding medium. Second shock formation is observed over the entire range from 100% Xe mass fraction to 100% N{sub 2}. The formation radius of the second shock as a function of Xe mass fraction is consistent with an analytical estimate.

• OSTI ID: 20860350
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 11 Vol. 13; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
LASER RADIATION
LIGHT TRANSMISSION
MACH NUMBER
MIXTURES
NITROGEN
OPACITY
PLASMA
PLASMA DENSITY
PLASMA EXPANSION
SHOCK WAVES
SPECIFIC HEAT
SPHERICAL CONFIGURATION
SUPERSONIC FLOW
THERMODYNAMICS
TRANSONIC FLOW
XENON