4 Matching Results

Results open in a new window/tab.

LLE Review, Quarterly Report: Volume 72, July-September 1997 (open access)

LLE Review, Quarterly Report: Volume 72, July-September 1997

This volume of the LLE Review, covering the period July--September 1997, begins with a general introduction to LLE`s experimental physics program and a report on recent results. This article includes a useful summary of the system`s operational capabilities and system parameters. Other highlights of the wide variety of research presented in this issue are: a promising method to directly observe the cold compressed shell of an imploding target. The shell is normally observed by backlighting. The proposal described here is to use a high-Z dopant that fluoresces under radiation from the hot core in the K{alpha} line. A study of the instabilities associated with near-forward stimulated Brillouin scattering. It includes a calculation of the saturation times and steady-state gain exponents. A successful program of pulse shaping for the OMEGA laser system. Examples of a variety of pulse shapes that can be programmed are presented. A description of the angular-scattering characteristics of ferroelectric liquid crystal electro-optical devices operating in transient and extended scattering modes. The possibility of applying these devices as modulators in practical IR imaging systems is evaluated. A faster method of shaping and finishing IR materials by the use of magnetorheological fluids. Detailed specifications and test results are included. …
Date: February 1, 1998
Creator: unknown
System: The UNT Digital Library
LLE Review, Quarterly Report: Volume 73, October-December 1997 (open access)

LLE Review, Quarterly Report: Volume 73, October-December 1997

This progress report contains discussion on the following topics: A high-bandwidth electrical-waveform generator based on aperture-coupled striplines for OMEGA pulse-shaping applications; sweep deflection circuit development using computer-aided circuit design for the OMEGA multichannel streak camera; D-{sup 3}He protons as a diagnostic for target {rho}R; growth rates of the ablative Rayleigh-Taylor instability in inertial confinement fusion; three-dimensional analysis of the power transfer between crossed laser beams; characterization of freestanding polymer films for application in 351-nm, high-peak-power laser systems; subsurface damage in microgrinding optical glasses; bound-abrasive polishers for optical glass; and color gamut of cholesteric liquid crystal films and flakes by standard colorimetry.
Date: April 1, 1998
Creator: Jacobs, Stephen D.
System: The UNT Digital Library
LLE Review, Quarterly Report: Volume 77, October-December 1998 (open access)

LLE Review, Quarterly Report: Volume 77, October-December 1998

This volume of the LLE Review, covering the period October--December 1998, includes two articles addressing issues applicable to direct-drive ICF on the National Ignition Facility (NIF): laser-plasma interactions and laser-irradiation uniformity. Additional highlights of the research presented in this issue are: (1) P.B. Radha and S. Skupsky present a novel charged-particle diagnostic that performs simultaneous {rho}R measurements of the fuel, shell, and ablator regions of a compressed ICF target, consisting of an inner DT fuel region, a plastic (CH) shell, and an ablator (CD), by measuring the knock-on deuteron spectrum. (2) F. Dahmani, S. Burns, J. Lambropoulos, S. Papernov, and A. Schmid report results from stress-inhibited laser-driven crack propagation and stress-delayed damage-initiation experiments in fused silica at 351 nm. Research is underway presently to determine the ramifications of these findings for large-aperture systems, such as OMEGA. (3) V. Goncharov presents an analytic theory of the ablative Richtmyer-Meshkov instability, which shows that the main stabilizing mechanism of the ablation-front perturbations is the dynamic overpressure of the blowoff plasma with respect to the target material. The perturbation evolution during the shock transit time is studied to determine the initial conditions for the Rayleigh-Taylor phase of the instability and to analyze the level …
Date: December 31, 1998
Creator: Regan, S. P.
System: The UNT Digital Library
LLE Review, Quarterly Report: Volume 74, January-March 1998 (open access)

LLE Review, Quarterly Report: Volume 74, January-March 1998

This volume of the LLE Review covers the period January--March 1998. The first of eight articles documents the in-house development, scale-up, and manufacture of 60 continuous distributed phase plates with high laser-damage resistance. D.J. Smith et al. describe how inert ion beams were used to etch a continuously varying pattern into the surface of fused silica to form these devices. Other highlights of research presented in this issue are: (1) a soft x-ray microscope with high spatial resolution has been characterized and used for initial experiments on the OMEGA laser system, F.J. Marshall et al. give details of the testing, calibration, and initial use of this microscope for studying the hydrodynamic stability of directly driven planar foils; (2) D.K. Bradley et al. report on a series of experiments designed to investigate hydrodynamic instability growth in direct-drive capsule implosions; (3) C.J. McKinstrie et al. report on the use of systematic perturbation methods to derive formulas for the Landau damping rates of electron-plasma and ion-acoustic waves; (4) high efficiency and good beam quality are potential advantages of the end-pumped solid-state lasers over the side-pumped ones, A. Babushkin et al. describe their successful use of a transport fiber to end-pump a Nd:YLF laser, …
Date: July 1, 1998
Creator: Jacobs, S. D.
System: The UNT Digital Library