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in creator/contributor: "Munro, D."

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Influence and measurement of mass ablation in ICF implosions

Point design ignition capsules designed for the National Ignition Facility (NIF) currently use an x-ray-driven Be(Cu) ablator to compress the DT fuel. Ignition specifications require that the mass of unablated Be(Cu), called residual mass, be known to within 1% of the initial ablator mass when the fuel reaches peak velocity. The specifications also require that the implosion bang time, a surrogate measurement for implosion velocity, be known to +/- 50 ps RMS. These specifications guard against … more

Date: September 5, 2007

Creator: Spears, B. K.; Hicks, D.; Velsko, C.; Stoyer, M.; Robey, H.; Munro, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutron spectrometry - An essential tool for diagnosing implosions at the National Ignition Facility

DT neutron yield (Y{sub n}), ion temperature (T{sub i}) and down-scatter ratio (dsr) determined from measured neutron spectra are essential metrics for diagnosing the performance of Inertial Confinement Fusion (ICF) implosions at the National Ignition Facility (NIF). A suite of neutron-Time-Of-Flight (nTOF) spectrometers and a Magnetic Recoil Spectrometer (MRS) have been implemented in different locations around the NIF target chamber, providing good implosion coverage and the redundancy requir… more

Date: May 2, 2012

Creator: Mackinnon, A. J.; Johnson, M. G.; Frenje, J. A.; Casey, D. T.; Li, C. K.; Seguin, F. H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

X-ray radiographic imaging of hydrodynamic phenomena in radiation driven materials -- shock propagation, material compression and shear flow. Revision 1

One- and two-dimensional, time resolved x-ray radiographic imaging at high photon energy (5-7 keV) is used to study shock propagation, material motion and compression, and the effects of shear flow in solid density samples which are driven by x-ray ablation with the Nova laser. By backlighting the samples with x-rays and observing the increase in sample areal density due to shock compression, the authors directly measure the trajectory of strong shocks ({approx}40 Mbar) in flight, in solid dens… more

Date: February 1, 1994

Creator: Hammel, B. A.; Kilkenny, J. D.; Munro, D.; Remington, B. A.; Kornblum, H. N.; Perry, T. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The First Experiments on the National Ignition Facility

A first set of laser-plasma interaction, hohlraum energetics and hydrodynamic experiments have been performed using the first 4 beams of the National Ignition Facility (NIF), in support of indirect drive Inertial Confinement Fusion (ICF) and High Energy Density Physics (HEDP). In parallel, a robust set of optical and x-ray spectrometers, interferometer, calorimeters and imagers have been activated. The experiments have been undertaken with laser powers and energies of up to 8 TW and 17 kJ in fl… more

Date: November 11, 2005

Creator: Landen, O. L.; Glenzer, S.; Froula, D.; Dewald, E.; Suter, L. J.; Schneider, M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Increasing robustness of indirect drive capsule designs against short wavelength hydrodynamic instabilities

Target designs are described that are meant to achieve ignition on the National Ignition Facility. Simulations of recent indirect drive cryogenic capsule designs indicate dramatically reduced growth of short wavelength hydrodynamic instabilities, resulting from two changes in the designs. First, better optimization results from systematic mapping of the ignition target performance over the parameter space of ablator and DT-ice thickness combinations, using techniques developed by one of us (Her… more

Date: November 12, 2004

Creator: Haan, S. W.; Herrmann, M. C.; Dittrich, T. R.; Fetterman, A. J.; Marinak, M. M.; Munro, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design and simulations of indirect drive ignition targets for NIF

No Description Available.

Date: October 28, 2004

Creator: Haan, S. W.; Amendt, P. A.; Dittrich, T. R.; Hammel, B. A.; Hatchett, S. P.; Herrmann, M. C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Exploring the Limits to NIF Capsule Coupling

Our original ignition ''point designs'' (circa 1992) for the National Ignition Facility (NIF) were made energetically conservative to provide margin for uncertainties in laser absorption, x-ray conversion efficiency and hohlraum-capsule coupling. Since that time, extensive experiments on Nova and Omega and their related analysis indicate that NIF coupling efficiency may be almost ''as good as we could hope for''. Given close agreement between experiment and theory/modeling, we can credibly expl… more

Date: November 3, 1999

Creator: Suter, L.; Rothenberg, J.; Munro, D.; Van Wonterghem, B. & Haan, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Electron thermal conduction in LASNEX

This report is a transcription of hand-written notes by DM dated 29 January 1986, transcribed by SW, with some clarifying comments added and details specific to running the LASNEX code deleted. Reference to the esoteric measurement units employed in LASNEX has also been deleted by SW (hopefully, without introducing errors in the numerical constants). The report describes the physics equations only, and only of electron conduction. That is, it does not describe the numerical method, which may be… more

Date: December 16, 1994

Creator: Munro, D. & Weber, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Progress in Long Scale Length Laser-Plasma Interactions

The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 mm and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3{omega}) with a total intensity of 2 x 10{sup 15} W cm{sup -2}. The targets were filled with 1 atm of CO{sub 2} producing of up to 7 mm long homogeneous… more

Date: November 11, 2003

Creator: Glenzer, S. H.; Arnold, P.; Bardsley, G.; Berger, R. L.; Bonanno, G.; Borger, T. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

3(omega) Power Balance Procedure on the NIF

This document defines the detailed NIF full system shot procedure to obtain 8% power balance as specified by the SDR002 3.2.1.04. Because the 48 quads of the NIF will be set up over a period of five years, obtaining power balance will naturally be accomplished in two steps. First, as each quad is brought online, the four laser beams within each quad will be tuned by setting the PABTS splitter ratios so that each beam will give the same laser power on target during low energy square pulse shots.… more

Date: January 22, 2001

Creator: Glenzer, S.; Jones, O.; Speck, D. R.; Munro, D.; Lerche, R.; Salmon, T. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Update on Indirect Drive Ignitin Target Design for NIF

Recent ignition target design effort has emphasized systematic exploration of the parameter space of possible ignition targets, providing as specific as possible comparisons between the various targets. This is to provide guidance for target fabrication R&D, and for the other elements of the ignition program. Targets are being considered that span 250-300 eV drive temperatures, capsule energies from 150 to 600 kJ, cocktail and gold hohlraum spectra, and three ablator materials (Be[Cu], CH[G… more

Date: October 21, 2003

Creator: Haan, S. W.; Amendt, P. A.; Dittrich, T. R.; Hammel, B. A.; Hatchett, S. P.; Herrmann, M. C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Update on NIF Indirect Drive Ignition Target Fabrication Specifications

Indirect drive ignition target simulations are described as they are used to determine target fabrication specifications. Simulations are being used to explore options for making the targets more robust, and to develop more detailed understanding of the performance of a few point designs. The current array of targets is described. A new target is described with radially dependent Cu dopant in Be. This target has significantly looser specifications for high-mode perturbations than previous targe… more

Date: October 17, 2003

Creator: Haan, S. W.; Amendt, P. A.; Dittrich, T. R.; Hatchett, S. P.; Herrmann, M. C.; Hurricane, O. A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

3D HYDRA simulations of NIF targets

The performance of NIF target designs is simulated in three dimensions using the HYDRA multiphysics radiation hydrodynamics code. In simulations of a cylindrical NIF hohlraum that include an imploding capsule, all relevant hohlraum features and the detailed laser illumination pattern, the motion of the wall material inside the hohlraum shows a high degree of axisymmetry. Laser light is able to propagate through the entrance hole for the required duration of the pulse. Gross hohlraum energetics … more

Date: October 30, 2000

Creator: Marinak, M. M.; Kerbel, G. D.; Gentile, N. A.; Jones, O.; Munro, D.; Pollaine, S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Feasibility of High Yield / High Gain NIF Capsules

Date: December 6, 1999

Creator: Suter, L.; Rothenberg, J.; Munro, D.; Van Wonterghem, B.; Haan, S. & Lindl, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department