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Measurements of magneto-Rayleigh-Taylor instability growth during the implosion of initially solid metal liners

Physics of Plasmas

Sinars, Daniel S.; Edens, Aaron E.; Lopez, Mike R.; Smith, Ian C.; Shores, Jonathon S.; Slutz, Stephen A.; Bennett, Guy R.; Atherton, B.W.; Savage, Mark E.; Stygar, William A.; Leifeste, Gordon T.; Herrmann, Mark H.; McBride, Ryan D.; Cuneo, M.E.; Jennings, Christopher A.; Peterson, Kyle J.; Vesey, Roger A.; Nakhleh, Charles N.

Abstract not provided.

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TYPE Journal Article YEAR 2010
OSTI

Measurements of Magneto-Rayleigh-Taylor instability growth in solid liners on the 20 MA Z facility

Sinars, Daniel S.; Edens, Aaron E.; Lopez, Mike R.; Smith, Ian C.; Shores, Jonathon S.; Bennett, Guy R.; Atherton, B.W.; Savage, Mark E.; Stygar, William A.; Leifeste, Gordon T.; Slutz, Stephen A.; Herrmann, Mark H.; Cuneo, M.E.; Peterson, Kyle J.; McBride, Ryan D.; Vesey, Roger A.; Nakhleh, Charles N.; Tomlinson, Kurt T.

The magneto-Rayleigh-Taylor (MRT) instability is the most important instability for determining whether a cylindrical liner can be compressed to its axis in a relatively intact form, a requirement for achieving the high pressures needed for inertial confinement fusion (ICF) and other high energy-density physics applications. While there are many published RT studies, there are a handful of well-characterized MRT experiments at time scales >1 {micro}s and none for 100 ns z-pinch implosions. Experiments used solid Al liners with outer radii of 3.16 mm and thicknesses of 292 {micro}m, dimensions similar to magnetically-driven ICF target designs [1]. In most tests the MRT instability was seeded with sinusoidal perturbations ({lambda} = 200, 400 {micro}m, peak-to-valley amplitudes of 10, 20 {micro}m, respectively), wavelengths similar to those predicted to dominate near stagnation. Radiographs show the evolution of the MRT instability and the effects of current-induced ablation of mass from the liner surface. Additional Al liner tests used 25-200 {micro}m wavelengths and flat surfaces. Codes being used to design magnetized liner ICF loads [1] match the features seen except at the smallest scales (<50 {micro}m). Recent experiments used Be liners to enable penetrating radiography using the same 6.151 keV diagnostics and provide an in-flight measurement of the liner density profile.

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TYPE Conference YEAR 2010
OSTI

Feasibility of measuring density and temperature of laser produced plasmas using spectroscopic techniques

Edens, Aaron E.

A wide variety of experiments on the Z-Beamlet laser involve the creation of laser produced plasmas. Having a direct measurement of the density and temperature of these plasma would an extremely useful tool, as understanding how these quantities evolve in space and time gives insight into the causes of changes in other physical processes, such as x-ray generation and opacity. We propose to investigate the possibility of diagnosing the density and temperature of laser-produced plasma using temporally and spatially resolved spectroscopic techniques that are similar to ones that have been successfully fielded on other systems. Various researchers have measured the density and temperature of laboratory plasmas by looking at the width and intensity ratio of various characteristic lines in gases such as nitrogen and hydrogen, as well as in plasmas produced off of solid targets such as zinc. The plasma conditions produce two major measurable effects on the characteristic spectral lines of that plasma. The 1st is the Stark broadening of an individual line, which depends on the electron density of the plasma, with higher densities leading to broader lines. The second effect is a change in the ratio of various lines in the plasma corresponding to different ionization states. By looking at the ratio of these lines, we can gain some understanding of the plasma ionization state and consequently its temperature (and ion density when coupled with the broadening measurement). The hotter a plasma is, the higher greater the intensity of lines corresponding to higher ionization states. We would like to investigate fielding a system on the Z-Beamlet laser chamber to spectroscopically study laser produced plasmas from different material targets.

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TYPE SAND Report YEAR 2008
DOIOSTI

Z-Beamlet: a multi-KJ TW-class laser for backlit x-radiography applications on the Z-Accelerator

Atherton, B.W.; Gonzales, Rita A.; Gurrieri, Thomas G.; Herrmann, Mark H.; Mulville, Thomas D.; Neely, Kelly A.; Rambo, Patrick K.; Rovang, Dean C.; Ruggles, Larry R.; Smith, Ian C.; Schwarz, Jens S.; Simpson, Walter W.; Sinars, Daniel S.; Speas, Christopher S.; Tafoya-Porras, Belinda T.; Wenger, D.F.; Young, Ralph W.; Adams, Richard G.; Bennett, Guy R.; Campbell, David V.; Carroll, Malcolm; Claus, Liam D.; Edens, Aaron E.; Geissel, Matthias G.

Abstract not provided.

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TYPE Conference YEAR 2007
OSTI

X-ray optics on the Z-Accelerator backlit with the Z-Beamlet Laser & Z-Petawatt Laser systems

Gonzales, Rita A.; Gurrieri, Thomas G.; Herrmann, Mark H.; Mulville, Thomas D.; Neely, Kelly A.; Rambo, Patrick K.; Rovang, Dean C.; Ruggles, Larry R.; Schwarz, Jens S.; Adams, Richard G.; Simpson, Walter W.; Sinars, Daniel S.; Smith, Ian C.; Speas, Christopher S.; Tafoya-Porras, Belinda T.; Wenger, D.F.; Young, Ralph W.; Edens, Aaron E.; Atherton, B.W.; Bennett, Guy R.; Campbell, David V.; Carroll, Malcolm; Claus, Liam D.; Geissel, Matthias G.

Abstract not provided.

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TYPE Conference YEAR 2007
OSTI
Results 26–50 of 57
Results 26–50 of 57