Laboratory observation of secondary shock formation ahead of a strongly radiative blast wave

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

DOI:https://doi.org/10.1063/1.2168157· OSTI ID:20782487

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

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

High Mach number blast waves were created by focusing a laser pulse on a solid pin, surrounded by nitrogen or xenon gas. In xenon, the initial shock is strongly radiative, sending out a supersonic radiative heat wave far ahead of itself. The shock propagates into the heated gas, diminishing in strength as it goes. The radiative heat wave also slows, and when its Mach number drops to two with respect to the downstream plasma, the heat wave drives a second shock ahead of itself to satisfy mass and momentum conservation in the heat wave reference frame; the heat wave becomes subsonic behind the second shock. For some time both shocks are observed simultaneously. Eventually the initial shock diminishes in strength so much that it can longer be observed, but the second shock continues to propagate long after this time. This sequence of events is a new phenomenon that has not previously been discussed in the literature. Numerical simulation clarifies the origin of the second shock, and its position is consistent with an analytical estimate.

• OSTI ID: 20782487
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 2 Vol. 13; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
LASER RADIATION
LASERS
MACH NUMBER
NITROGEN
PLASMA
PLASMA HEATING
PLASMA SIMULATION
PULSES
SHOCK WAVES
XENON