WorldCat Identities

Gardner, J. H.

Overview
Works: 50 works in 55 publications in 1 language and 58 library holdings
Genres: Maps 
Roles: Author
Publication Timeline
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Most widely held works by J. H Gardner
Map of oil and gas structure at Lewisburg and Epley, Todd and Logan counties, Ky. by J. H Gardner( )

1 edition published in 1919 in English and held by 3 WorldCat member libraries worldwide

The Rayleigh-Taylor and Kelvin-Helmholtz Instabilites in Targets Accelerated by Laser Ablation by M. H Emery( Book )

2 editions published in 1981 in English and held by 2 WorldCat member libraries worldwide

Using the FAST2D laser-shell simulation model we have accelerated a 20 micrometer thick plastic foil up to 160 km/s. The foil maintained its integrity up to 10 ns giving an aspect ratio of 40. We are able to follow the Rayleigh-Taylor bubble-and-spike development far into the nonlinear regime and beyond the point of foil fragmentation. Strong shear flow develops at the interface between the bubble-and-spike which leads to the development of the Kelvin-Helmholtz instability. The K-H instability causes the tips of the spikes to widen and as a result reduce their rate of 'fall.' (Author)
A Pocket check list of perforation varieties of King George VI postage stamps, excluding the Dominions( Book )

1 edition published in 1949 in English and held by 2 WorldCat member libraries worldwide

Steady-state planar ablative flow by Wallace M Manheimer( Book )

2 editions published in 1981 in English and held by 2 WorldCat member libraries worldwide

Steady state planar ablative flow in a laser produced plasma is studied. Our calculations relate all steady state fluid quantities to only three parameters, the material, absorbed irradiance and laser wavelength. The fluid is broken into three regions; the subcritical expanding plasma, the steady state ablation front and the accelerated slab. Boundary conditions at the interfaces of these regions are given. If the absorbed irradiance is nonuniform, the nonuniformity in ablation pressure is calculated. Results are compared with experiment and fluid simulation for both uniform and nonuniform illumination. (Author)
Palmer by J. H Gardner( Book )

1 edition published in 2011 in English and held by 2 WorldCat member libraries worldwide

The nonlinear aspects of the Rayleigh-Taylor instability in laser ablation by M. H Emery( Book )

2 editions published in 1982 in English and held by 2 WorldCat member libraries worldwide

We report on our investigation of the Rayleigh-Taylor (R-T) and Kelvin-Helmholtz (K-H) instabilities in laser ablatively accelerated targets for single mode perturbations for a series of wavelengths in the parameter regime 1/2 less than or equal to lambda/delta R less than or equal to 10, where lambda is the wavelength of the perturbation and delta is the cold foil thickness. We find linear growth rates well below classical values (by a factor on the order of 3-4). We also find a cutoff in the growth rates for wavelengths less than the foil thickness. The striking result is the dominance of nonlinear effects; i.e., the K-H instability for short wavelength perturbations. Although the linear growth rates increase as k1/2 up to the cutoff, the K-H rollup dominates at large k, drastically reducing the penetration rate of the dense spike below its free fall value and effectively doubling the aspect ratio of the foil. In other words, it is the long wavelength perturbations that are most effective in destroying the symmetric implosion of the shell
Wavelength Scaling for Reactor-Size Laser Fusion Targets by J. H Gardner( Book )

2 editions published in 1981 in English and held by 2 WorldCat member libraries worldwide

The symmetric implosion of pellet shells will require sideways thermal transport smoothing of any laser intensity nonuniformities. A scaling law shows a surprisingly strong laser wavelength dependence for this smoothing mechanism; it places a large premium on the use of longer wavelength near-infrared lasers. This smoothing requirement conflicts with the advantages of shorter laser wavelengths for controlling deleterious plasma instabilities. (Author)
Laser interaction in long-scalelength plasmas( Book )

2 editions published in 1985 in English and held by 2 WorldCat member libraries worldwide

Absorption of a short-pulse, high-intensity Nd-laser beam (vacuum irradiance of 10 to the 14th power to 10 to the 15th power W/sq cm) by preformed plasmas of different density scalelengths is investigated. Increased effects of plasma instabilities are found at longer scalelengths. The amount of backscattered light increases with plasma scalelength and limits the absorption fraction at the longest scalelength. The onset of suprathermal electron production, deduced from observations of energetic (20 to 50 keV) x rays, occurs at lower laser irrradiance for longer scalelength plasmas. A correlation between energetic x rays and 3 omega sub 0/2 emission suggests that the suprathermal electrons are produced by a plasma instability at quarter-critical density. At higher intensities there is evidence for severe perturbations of the preformed plasma and for self-focusing of the incident beam. Keywords: Long scalelength; Laser plasma interaction; Stimulated brillouin backscatter; Laser absorption
X-Ray Production in Long-Scalelength Laser-Plasma Interaction Experiments( Book )

1 edition published in 1983 in English and held by 1 WorldCat member library worldwide

Measurements of x-rays produced in longer-scalelength interaction experiments carried out using the NRL Pharos II Nd laser facility are described in this presentation
A Numerical Solution Technique for Multitemperature Plasma Hydrodynamics( Book )

1 edition published in 1985 in English and held by 1 WorldCat member library worldwide

We describe a numerical technique for the solution of the equations of multitemperature plasma hydrodynamics in a finite-difference formulation. A key feature of the algorithm is that it is locally mass, momentum, and energy conservative, and therefore is particularly useful for problems which require an accurate description of each of the constitutent fluids in the presence of shock waves. We present explicit formulae for solving the equations for a simple two-temperature plasma, and discuss the extension of the algorithm to more complex multitemperature plasma models. We also summarize some results from a two-temperature laser-matter interaction simulation as an illustration of the performance of the algorithm
Vortex Shedding and Laser Ablation( Book )

1 edition published in 1983 in English and held by 1 WorldCat member library worldwide

Through a critical examination of the vortex dynamics of laser ablatively accelerated targets the author was able to explain the inhibited linear Rayleigh-Taylor growth rates, clarify the role fo the Kelvin-Helmholtz roll-up, explain the short wavelength cutoff, explain and theoretically reproduce dynamically stabilized growth rates and predict magnetic field structures throughout the overdense region which lead to a physically motivated model of thermal flux inhibition
Coal fields in Colorado and New Mexico : coal of the Denver Basin, Colo.( Book )

1 edition published in 1910 in English and held by 1 WorldCat member library worldwide

Simulation of Laser Beam Nonuniformity Effects( Book )

1 edition published in 1981 in English and held by 1 WorldCat member library worldwide

We investigate the effect of a nonuniform beam on the ablative acceleration of thin foils using the FAST2D laser-shell simulation code. The results show that laser nonuniformities with scalelengths greater than the distance from the ablation surface to the critical surface would have a severe impact on drive pressure symmetry and hence on pellet gain. (Author)
Coal fields of Colorado, New Mexico, Utah, Oregon, and Virginia : coal fields of northwestern Colorado and northeastern Utah( Book )

1 edition published in 1909 in English and held by 1 WorldCat member library worldwide

Recolonisation of rehabilitated bauxite mine sites in western Australia by mycorrhizal fungi by J.H Gardner( )

in English and held by 1 WorldCat member library worldwide

Development of a Lagrangian quasi-static two-demensional Tokamak model by J. H Gardner( Book )

1 edition published in 1975 in English and held by 1 WorldCat member library worldwide

Flame ion conference at princeton, october 12-13, 1959( Book )

1 edition published in 1959 in English and held by 1 WorldCat member library worldwide

Summaries are given of papers presented at the conference
High-Gain Direct-Drive Target Design for Laser Fusion (Preprint)( )

1 edition published in 2000 in English and held by 0 WorldCat member libraries worldwide

We have developed a new direct-drive target design that has a predicted energy gain of 127 using a 1.3 MJ KrF laser and a gain of 155 using 3.1 MJ. The DT fuel is surrounded by an ablator consisting of a low density CH foam filled with frozen DT. The ablator is then surrounded by a thin CH coating and a very thin high-Z overcoat. The energy gain of 127-155 is possible through the use of (1) direct-drive laser-target coupling; (2) controlled levels of radiative preheating that keeps the DT fuel on a low isentrope (3) a short 1/4 micrometer laser wavelength for maximum absorption and rocket efficiencies (4) reduction of the laser beam focal spot size during the implosion (zooming) so that the focal spot size better matches the imploding target size and (5) ISI optical smoothing to minimize the laser nonuniformities at both high and low mode numbers. In addition to its high energy gain this target design has several other attractive features: a low target fabrication cost through the use of a few simple target materials; the potential for a modest-size 300 MWe power plant the target's physical strength to withstand the acceleration into the chamber and a high infrared albedo to better protect the target from preheating during the injection into the chamber
Direct-Drive Laser Target Designs for Sub-MegaJoule Energies( )

1 edition published in 2007 in English and held by 0 WorldCat member libraries worldwide

New direct-drive laser target designs with KrF laser light take advantage of the shorter wavelength to lower the laser energy required for substantial gain (>30x) to sub-MJ level. These low laser-energy pellets are useful in systems that could form an intermediate step towards fusion energy, such as the proposed Fusion Test Facility [S.P. Obenschain, et al, Phys. Plasmas 13, 056320 (2006)]. The short wavelength laser should allow higher intensity (and higher pressure) without increasing the risk of laser-plasma instabilities. The higher pressure in turn allows higher velocities to be achieved while keeping the low aspect ratios required for hydrodynamic stability. The canonical laser energy has been chosen to be 500 kJ. A target design is presented with various laser pulse shapes and both 1D and 2D simulation results are shown. The sensitivity of these targets to both low-mode and high-mode perturbations is examined. The analysis and simulations in this paper indicate that significant gain (G=57) can be achieved for these targets even in the presence of hydrodynamic instabilities
 
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English (25)