Search Results

Advanced search parameters have been applied.
open access

X-ray laser studies using plasmas created by optical field ionization

Description: X-ray laser experiments involving the creation of fast recombining plasmas by optical field ionization of preformed targets were conducted. A nonlinear increase in the intensity of the 13.5nm Lyman-{alpha} line in Li III with the length of the target plasma was observed but only for distances less than the laser confocal parameter and for low plasma electron temperatures. Multiphoton pumping of resonant atomic transitions was also examined and the process of multiphoton ionization of FIII was f… more
Date: January 1, 1995
Creator: Krushelnick, K. M.; Tighe, W. & Suckewer, S.
Partner: UNT Libraries Government Documents Department
open access

Plasma production and flow in negative ion beams

Description: Plasma generated in low-density vapor by a negative ion beam has been studied experimentally and computationally. We show that space charge neutralization of the beam occurs at very low vapor density, and that correspondingly the electron density may be much less than the beam and plasma ion densities. When there is a large local gas density, as in a charge changing cell, the resulting high electron density is also localized to the same region. Therefore, very few electrons will reach a negativ… more
Date: September 21, 1977
Creator: Anderson, O. A. & Hooper, E. B. Jr.
Partner: UNT Libraries Government Documents Department
open access

High efficiency ionizer using a hollow cathode discharge plasma

Description: A proposal for an ionizer using a hollow cathode discharge plasma is described. Ionization is via the very high current density electron beam component in the plasma, as well as from charge exchange with plasma ions. Extraction of a He/sup +/ current corresponding to approximately 50% of the incoming atomic beam flux should be possible.
Date: January 1, 1984
Creator: Alessi, J.G. & Prelec, K.
Partner: UNT Libraries Government Documents Department
open access

System requirements for the Los Alamos foil-implosion project

Description: The goal of the Los Alamos imploding foil project is the development of an intense source of soft x rays and hot plasma produced from the thermalization of 1 to 10 MJ of plasma kinetic energy. The source will be used for material studies and fusion experiments. Specifically, thin, current-carrying cylindrical metallic plasmas are imploded via their self-magnetic forces. Features of this project are the use of high-explosive-driven flux-compression generators as the prime power source to achieve… more
Date: January 1, 1983
Creator: Brownell, J.; Bowers, R.; Greene, A.; Lindemuth, I.; Nickel, G.; Oliphant, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Design and fabrication of a 30 second pulsed plasma generator

Description: The design and fabrication techniques for a large hybrid magnetic cusp plasma generator developed for 30 sec pulse length are described. Included are the magnetic cusp geometry features, water cooling characteristics, filament structures, and the high energy density actively cooled anode and electron dump employed.
Date: October 1, 1983
Creator: Biagi, L. A.; Ehlers, K. W.; Lietzke, A. F.; Matuk, C. A.; Maruyama, Y.; Paterson, J. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Plasma production from shock compression of condensed matter

Description: The experimental investigation of HE-driven, phased, cylindrical, SS liner implosion has yielded many interesting results. Plasma and radiation are found to be copiously produced. Plasmas with velocity up to 17 cm/{mu}s are observed. The temperature in the expansion surface reaches 8 - 10 eV and stays hot for tens of microseconds. The signatures of plasma interactions with the imploding wall and the glass port are clearly identified. Finally, a cluster of cooler but still self-luminous, high-de… more
Date: September 1, 1995
Creator: Tan, T. H. & Marsh, S. P.
Partner: UNT Libraries Government Documents Department
open access

Method of forming a thin unbacked metal foil

Description: The present invention relates generally to metal foils and methods of making the same. More particularly, this invention pertains to the fabrication of very thin, unbacked metal foils.
Date: February 23, 1983
Creator: Duchane, D. V. & Barthell, B. L.
Partner: UNT Libraries Government Documents Department
open access

Electron beam expansion by target heating

Description: An intense, pulsed, relativistic electron beam can heat a thin metal plate to a plasma state as it traverses. This rapid heating creates a large radial temperature gradient in the material. As heat flow is primarily by electron motion, currents arise because of the thermal gradient. This effect magnetizes the target material during the course of the beam. If this magnetization exceeds that of the vacuum field of the electron beam then it dominates beam dynamics within the material. Plasmas of i… more
Date: July 2, 1998
Creator: Garcia, M
Partner: UNT Libraries Government Documents Department
open access

Composite wire plasma formation and evolution

Description: The detailed understanding of the formation and evolution of plasma from rapidly heated metallic wires is a long-standing challenge in the field of plasma physics and in exploding wire engineering. This physical process is made even more complicated if the wire material is composed of a number of individual layers. The authors have successfully developed both optical and x-ray backlighting diagnostics. In particular, the x-ray backlighting technique has demonstrated the capability for quantitat… more
Date: January 1, 2000
Creator: Spielman, Rick B.
Partner: UNT Libraries Government Documents Department
open access

Vacuum-spark metal ion source based on a modified Marx generator

Description: The plasma generating parts of ion sources including their power supplies are usually floated to high potential (ion extraction voltage), thus requiring great insulation efforts and high costs for high-energy ion beams. A new concept for pulsed ion sources is presented in which a single power supply is used to simultaneously produce the plasma and high extractor voltage via a modified Marx generator. Proof-of-principle experiments have been performed with high-current spark discharges in vacuum… more
Date: April 1, 1996
Creator: Anders, A.; Brown, I.G.; MacGill, R.A. & Dickinson, M.R.
Partner: UNT Libraries Government Documents Department
open access

Metallization technology for tenth-micron range integrated circuits. CRADA final report for CRADA number ORNL92-0104

Description: A critical step in the fabrication of integrated circuits is the deposition of metal layers which interconnect the various circuit elements that have been formed in earlier process steps. In particular, columns of metal 2-3 times higher than the characteristic dimension of the circuit are needed. At the time of initiation of this CRADA, the state-of-the-art was the production of 1-1.5 micron-high columns for 0.5 micron-wide features with an expected reduction in size by a factor of two or more … more
Date: April 11, 1996
Creator: Berry, L.A.; Gorbatkin, S.M.; Rossnagel, S.M. & Harper, J.M.E.
Partner: UNT Libraries Government Documents Department
open access

RF heating experiments in CHS and RF development for LHD

Description: The Lame Helical Device, LHD, is in its final construction phase. It is a 1=2, m=10 Heliotron/Torsatron type helical system with a major radius of 4 m. The compact helical system, CHS, is a 1=2, m=8 helical system of the same type with a major radius of 1m. CHS has been used for supporting experiments to clarify physics issues of helical systems and to examine the key ideas which will be applied to LHD. This paper summarizes the experimental results of those supporting experiments in CHS and ho… more
Date: April 1, 1997
Creator: Watari, T.; Kumazawa, R. & Nishimura, K.
Partner: UNT Libraries Government Documents Department
open access

Magnetic compression/magnetized target fusion (MAGO/MTF), an update

Description: Magnetized Target Fusion (MTF) was reported in two papers at the First Symposium on Current Trends in International Fusion Research. MTF is intermediate between two very different mainline approaches to fusion: Inertial Confinement Fusion (ICF) and magnetic confinement fusion (MCF). The only US MTF experiments in which a target plasma was compressed were the Sandia National Laboratory ``Phi targets``. Despite the very interesting results from that series of experiments, the research was not pur… more
Date: March 1, 1998
Creator: Kirkpatrick, R.C. & Lindemuth, I.R.
Partner: UNT Libraries Government Documents Department
open access

Modeling of profile effects for the LLNL Large Area Inductively Coupled Plasma Source

Description: Inductively coupled plasma (ICP) sources are one of the most important high density plasma configurations developed in recent years. Next generation technology requires plasma processing systems with high uniformity over very large areas. The authors present here a comparison between computer modeling and experimental results from the LLNL Large Area ICP Source. The LLNL experiment has a 30 inches diameter and is designed to study 400mm. processing. Computer simulations using the fluid code, IN… more
Date: May 1, 1995
Creator: Vitello, P.; Parker, G. J. & Tishchenko, N.
Partner: UNT Libraries Government Documents Department
open access

Energy distributions of electrons in electron beam produced nitrogen plasmas

Description: A theory was developed which predicts the equilibrium electron energy distributions resulting from the injection of an electron beam into molecular nitrogen. The results were highly non-Maxwellian with a depletion region existing near 2.5 eV. Using these distributions, fractional power transfers to various excitation processes were calculated. The theory was verified experimentally by using Langmuir probes to measure the electron energy distributions produced by a beam generated by a cold catho… more
Date: January 1, 1976
Creator: Suhre, D. R.
Partner: UNT Libraries Government Documents Department
open access

Magnetic-Compression/Magnetized-Target Fusion (Mago/Mtf): A Marriage of Inertial and Magnetic Confinement

Description: Intermediate between magnetic confinement (MFE) and inertial confinement (ICF) in time and density scales is an area of research now known in the US as magnetized target fusion (MTF) and in Russian as MAGO (MAGnitnoye Obzhatiye--magnetic compression). MAGO/MTF uses a magnetic field and preheated, wall-confined plasma fusion fuel within an implodable fusion target. The magnetic field suppresses thermal conduction losses in the fuel during the target implosion and hydrodynamic compression heating… more
Date: December 31, 1996
Creator: Lindemuth, I. R.; Ekdahl, C. A. & Kirkpatrick, R. C.
Partner: UNT Libraries Government Documents Department
open access

Parametric study of compound semiconductor etching utilizing inductively coupled plasma source

Description: Inductively Coupled Plasma (ICP) sources are extremely promising for large-area, high-ion density etching or deposition processes. In this review the authors compare results for GaAs and GaN etching with both ICP and Electron Cyclotron Resonance (ECR) sources on the same single-wafer platform. The ICP is shown to be capable of very high rates with excellent anisotropy for fabrication of GaAs vias or deep mesas in GaAs or GaN waveguide structures.
Date: July 1, 1996
Creator: Constantine, C.; Johnson, D. & Barratt, C.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen