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LLE Review, Quarterly Report: Volume 65, October-December 1995

Description: This volume of the LLE Review, covering the period October-December 1995, contains a description of the generation and characterization of continuous, deep-surface-relief phase plates that are more efficient and versatile than previous designs. The LLE program plan has scheduled a number of enhancements to OMEGA`s performance and uniformity, the first of which is the implementation of these new distributed phase plates. Other articles in this volume include the discussion of an x-ray diagnostic… more
Date: June 1, 1996
Creator: Boehly, T. R.
Partner: UNT Libraries Government Documents Department
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LLE Review, Quarterly Report: Volume 66, January-March 1996

Description: This volume of the LLE Review, covering the period January-March 1996, contains three articles related to spherical implosions and their diagnosis, one article that provides an analysis of laser-plasma interactions, and three articles on advanced technologies developed at LLE.
Date: June 1, 1996
Creator: Boehly, T. R.
Partner: UNT Libraries Government Documents Department
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Shock-Compressed Diamond: Melt, Insulator-Conductor and Polymeric-Atomic Transitions

Description: Temperatures measured on the shock-Hugoniot of diamond reveal melting between 650 ({+-} 60) GPa and 9000 ({+-} 800) K and 1090 ({+-} 50) GPa and 8400 ({+-} 800) K, with a heat of fusion of {approx} 25 {+-} 10 kJ/mole and a negative Clapeyron slope {partial_derivative}T/{partial_derivative}P|{sub melt} = -5 {+-} 3 K/GPa. Thus, the fluid is denser than the compressed solid, and optical reflectivity measurements show it to be metallic. Hugoniot-temperature measurements extending to over 4000 GPa (… more
Date: August 16, 2007
Creator: Eggert, J; Hicks, D G; Celliers, P M; Bradley, D K; McWilliams, R S; Jeanloz, R et al.
Partner: UNT Libraries Government Documents Department
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EXAFS Measurements of Laser-Shocked V and Ti and Crystal Phase Transformation in Ti

Description: Extended X-Ray Absorption Fine Structure (EXAFS), using a laser-imploded target as a source, can yield the properties of laser-shocked metals on a nanosecond time scale. EXAFS measurements of vanadium shocked to {approx}0.4 Mbar yield the compression and temperature in good agreement with hydrodynamic simulations and shock-speed measurements. In laser-shocked titanium at the same pressure, the EXAFS modulation damping is much higher than warranted by the predicted temperature increase. This is … more
Date: March 10, 2004
Creator: Yaakobi, B.; Meyerhofer, D. D.; Boehly, T. R.; Rehr, J. J.; Remington, B. A.; Allen, P. G. et al.
Partner: UNT Libraries Government Documents Department
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Properties of Fluid Deuterium under Double-Shock Compression to Several Mbar

Description: The compressibility of fluid deuterium up to several Mbar has been probed using laser-driven shock waves reflected from a quartz anvil. Combining high-precision ({approx} 1 %) shock velocity measurements with the double-shock technique, where differences in equation of state (EOS) models are magnified, has allowed us to accurately discriminate between various theoretical predictions. Our data are consistent with EOS models that show approximately fourfold compression on the principal Hugoniot f… more
Date: February 3, 2004
Creator: Vianello, E; Celliers, P M; Hicks, D G; Boehly, T R; Collins, T B; Moon, S J et al.
Partner: UNT Libraries Government Documents Department
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Multiple Film Plane Diagnostic for Shocked Lattice Measurements

Description: Laser-based shock experiments have been conducted in thin Si and Cu crystals at pressures above the Hugoniot Elastic Limit (HEL). In these experiments, static film and x-ray streak cameras recorded x-rays diffracted from lattice planes both parallel and perpendicular to the shock direction. This data showed uniaxial compression of Si (100) along the shock direction and 3-D compression of Cu (100). In the case of the Si diffraction, there was a multiple wave structure observed, which may be due … more
Date: July 2, 2002
Creator: Kalantar, D. H.; Bringa, E.; Caturla, M.; Colvin, J.; Lorenz, K. T.; Kumar, M. et al.
Partner: UNT Libraries Government Documents Department
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Studies of Dynamic Properties of Shock Compressed FCC Crystals by in Situ Dynamic X-Ray Diffraction

Description: There were 5 laser experiments conducted to date in FY-01 under the ongoing project to study the response of single crystal fcc materials under shock compression. An additional 10 laser shots are planned for August, 2001. This work has focused on developing capability to record diffraction from multiple lattice planes during the passage of a shock through a thin foil of single crystal copper, while simultaneously performing separate shock sample recovery experiments to study the residual deform… more
Date: August 14, 2001
Creator: Baldis, H.; Kalantar, D. H.; Remington, B. A.; Belak, J.; Colvin, J.; Boehly, T. R. et al.
Partner: UNT Libraries Government Documents Department
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Studies of dynamic properties of shock compressed single crystals by in situ dynamic x-ray diffraction and sample recovery

Description: Laser compression provides pressures ranging from a few to hundreds of GPa at pulse durations of the order of nanoseconds or fractions thereof. The short duration ensures a rapid decay of the pulse and quenching of shocked sample in times that are orders of magnitude lower than in conventional explosively driven plate impact experiments. Systematic experiments carried out in specimens well suited for transmission electron microscopy characterization are revealing that laser compression, by virt… more
Date: May 5, 2007
Creator: Meyers1, M. A.; Schneider, M. S.; Jarmakani, H.; Kad, B.; Remington2, B. A.; Kalantar, D. H. et al.
Partner: UNT Libraries Government Documents Department
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Experimental Studies of ICF Indirect-Drive Be and High Density C Candidate Ablators

Description: To validate our modeling of the macroscopic and microscopic hydrodynamic and equation of state response of these candidate ablators to NIC-relevant x-ray drive, a multi-lab experimental program has been verifying the behavior of these new ablators. First, the pressures for onset and termination of melt for both Be and HDC under single or double shock drive has been measured at the Z and Omega facilities. Second, the level and effect of hard x-ray preheat has been quantified in scaled experiment… more
Date: September 5, 2007
Creator: Landen, O. L.; Bradley, D. K.; Braun, D. G.; Smalyuk, V. A.; Hicks, D. G.; Celliers, P. M. et al.
Partner: UNT Libraries Government Documents Department
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Cryogneic-Target Performance and Implosion Physics Studies on OMEGA

Description: Recent progress in direct-drive cryogenic implosions on the OMEGA Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] is reviewed. Ignition-relevant areal densities of ~200 mg/cm^2 in cryogenic D2 implosions with peak laser-drive intensities of ~5 x 10^14 W/cm^2 were previously reported [T. C. Sangster et al., Phys. Rev. Lett. 100, 185006 (2008)]. The laser intensity is increased to ~10^15 W/cm^2 to demonstrate ignition-relevant implosion velocities of 3–4 x 10^7 cm/ s, providing… more
Date: March 6, 2009
Creator: Smalyuk, V. A.; Betti, R.; Boehly, T. R.; Craxton, R. S.; Delettrez, J. A.; Edgell, D. H. et al.
Partner: UNT Libraries Government Documents Department
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Direct-Drive Inertial Fusion Research at the University of Rochester's Laboratory for Laser Energetics: A Review

Description: This paper reviews the status of direct-drive inertial confinement fusion (ICF) research at the University of Rochester's Laboratory for Laser Energetics (LLE). LLE's goal is to demonstrate direct-drive ignition on the National Ignition Facility (NIF) by 2014. Baseline "all-DT" NIF direct-drive ignition target designs have been developed that have a predicted gain of 45 (1-D) at a NIF drive energy of ~1.6 MJ. Significantly higher gains are calculated for targets that include a DT-wicked foam ab… more
Date: April 16, 2010
Creator: McCrory, R. L.; Meyerhofer, D. D.; Loucks, S. J.; Skupsky, S.; Bahr, R. E.; Betti, R. et al.
Partner: UNT Libraries Government Documents Department
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Shock timing on the National Ignition Facility: First Experiments

Description: An experimental campaign to tune the initial shock compression sequence of capsule implosions on the National Ignition Facility (NIF) was initiated in late 2010. The experiments use a NIF ignition-scale hohlraum and capsule that employs a reentrant cone to provide optical access to the shocks as they propagate in the liquid deuterium-filled capsule interior. The strength and timing of the shock sequence is diagnosed with velocity interferometry that provides target performance data used to set … more
Date: October 24, 2011
Creator: Celliers, P. M.; Robey, H. F.; Boehly, T. R.; Alger, E.; Azevedo, S.; Berzins, L. V. et al.
Partner: UNT Libraries Government Documents Department
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