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in creator/contributor: "Schneider, M."

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Lorentz Angle Studies for the SLD Endcap Cerenkov Ring Imaging Detector

The design of the endcap Cerenkov Ring Imaging Detectors for SLD requires a detailed understanding of how electrons drift in gases under the influence of crossed electric and magnetic fields. In this report, we present recent measurements of Lorentz angles and drift velocities in gases suitable for the endcap CRID photon detectors. We compare these measurements to predictions from a theoretical model; good agreement is observed. Based on our results we present a design for detectors operating i… more

Date: November 1, 1987

Creator: Coyle, P.; Cavalli-Sforza, M.; Coyne, D.; Schneider, M.; Spencer, E.; Williams, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Electron-ion interaction cross sections determined by x-ray spectroscopy on EBIT

The Livermore electron beam ion trap (EBIT) is used to measure electron-ion interactions with high-resolution x-ray spectroscopy. Measurements are presented of the K{alpha} x-ray emission of heliumlike Fe{sup 24+} that demonstrate the effect of various processes on the spectrum of highly charged heliumlike ions. In particular, we have studied how dielectronic recombination into high-n Rydberg levels and resonance excitation processes contribute to the x-ray emission near threshold for direct el… more

Date: June 26, 1991

Creator: Beiersdorfer, P.; Cauble, R.; Chantrenne, S.; Chen, M.; Knapp, D.; Marrs, R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Uniqueness of Neumann-Tricomi problem in IR/sup 2/. Technical note BN-906. [Energy-integral method]

Using a variation of the energy-integral method sufficient conditions for the uniqueness of the solution of the Neumann-Tricomi boundary value problem are obtained. A uniqueness theorem is given for a general function. 11 references. (JFP)

Date: April 1, 1979

Creator: Aziz, A.K. & Schneider, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

The fluid systems for the SLD Cherenkov ring imaging detector

We describe the design and operation of the fluid delivery, monitor and control systems for the SLD barrel Cherenkov Ring Imaging Detector (CRID). The systems deliver drift gas (C{sub 2}H{sub 6} + TMAE), radiator gas (C{sub 5}F{sub 12} + N{sub 2}) and radiator liquid (C{sub 6}F{sub 14}). Measured critical quantities such as electron lifetime in the drift gas and ultra-violet (UV) transparencies of the radiator fluids, together with the operational experience, are also reported.

Date: October 1, 1992

Creator: Abe, K.; Hasegawa, K.; Hasegawa, Y.; Iwasaki, Y.; Suekane, F.; Yuta, H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Shielding a Streak Camera from Hard X-rays

The targets used in the Hot Halfraum Campaign at OMEGA create many hot electrons, which result in a large flux of hard x-rays. The hard x-rays produce a high background in the streak camera. The background was significantly reduced by wrapping the streak camera with a high-Z material; in this case, 1/8' of Pb. The large hard x-ray flux also adds noise to images from framing cameras which use CCDs.

Date: April 14, 2004

Creator: Schneider, M.; Sorce, C.; Loughman, K.; Emig, J.; Bruns, H.; Back, C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Application of Spatially Resolved High Resolution Crystal Spectrometry to ICF Plasmas

High resolution (λ/Δ#3;λ ~ 10 000) 1D imaging x-ray spectroscopy using a spherically bent crystal and a 2D hybrid pixel array detector is used world wide for Doppler measurements of ion-temperature and plasma flow-velocity profiles in magnetic confinement fusion plasmas. Meter sized plasmas are diagnosed with cm spatial resolution and 10 ms time resolution. This concept can also be used as a diagnostic of small sources, such as inertial confinement fusion plasmas and targets on x-ray light sour… more

Date: September 15, 2012

Creator: Hill, Kenneth W.; Bitter, M.; Delgado-Aprico, L.; Pablant, N. A.; Beirersdorfer, P.; Schneider, M. 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

Hydrodynamic instability experiments and simulations

Richtmyer-Meshkov experiments are conducted on the Nova laser with strong radiatively driven shocks (Mach > 20) in planar, two-fluid targets with Atwood number A < 0. Single mode interfacial perturbations are used to test linear theory and 3D random perturbations are used to study turbulent mix. Rayleigh-Taylor experiments are conducted on a new facility called the Linear Electric Motor (LEM) in which macroscopic fluids are accelerated electromagnetically with arbitrary acceleration profiles. T… more

Date: July 1, 1995

Creator: Dimonte, G.; Schneider, M. & Frerking, C.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Materials Science under Extreme Conditions of Pressure and Strain Rate

Solid state dynamics experiments at very high pressures (P >> 10 GPa) and strain rates ({var_epsilon} >> 10{sup 5} s{sup -1}) have been demonstrated on high energy laser facilities, albeit over brief intervals of time and small spatial scales. We have developed two methods for driving samples to high pressures (10-100 GPa) at high strain rate (10{sup 6}-10{sup 8} s{sup -1}) in the solid state. One method uses a shockless compression technique, and the other uses multiple staged shoc… more

Date: March 27, 2003

Creator: Remington, B. A.; Bazan, G.; Bringa, E.; Caturla, M.; Edwards, M. J.; Glendinning, S. G. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measuring the ionization balance of gold in a low-density plasma of importance to ICF

Charge state distributions (CSDs) have been determined in low density ({approx}10 {sup 12} cm{sup -3}) gold plasmas having either a monoenergetic beam (E{sub Beam} = 2.66, 3.53 and 4.54 keV) or experimentally simulated thermal electron distributions (T{sub e} = 2.0, 2.5 and 3.0 keV). These plasmas were created in the Livermore electron beam ion traps EBIT-I and EBIT-II. Line emission and radiative recombination features of Ni to Kr-like gold ions were recorded in the x-ray region with a crystal… more

Date: May 3, 2004

Creator: May, M.; Beiersdorfer, P.; Schneider, M.; Terracol, S.; Wong, K.; Fournier, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Multiple Film Plane Diagnostic for Shocked Lattice Measurements

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.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Gold Charge State Distributions in Highly Ionized, Low-Density Beam Plasmas

No Description Available.

Date: June 15, 2011

Creator: May, M. J.; Scofield, J.; Schneider, M.; Wong, K.; Beiersdorfer, P. & Hansen, S. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

X-ray flux and x-ray burnthrough experiments on reduced-scale targets at the NIF and OMEGA lasers

An experimental campaign to maximize radiation drive in small-scale hohlraums has been carried out at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (Livermore, CA USA) and at the OMEGA laser at the Laboratory for Laser Energetics (Rochester, NY USA). The small-scale hohlraums, laser energy, laser pulse, and diagnostics were similar at both facilities but the geometries were very different. The NIF experiments used on-axis laser beams whereas the OMEGA experi… more

Date: August 24, 2005

Creator: Schneider, M.; Hinkel, D.; Young, B.; Holder, J.; Langdon, A.; Baldis, H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High-pressure, High-strain-rate Materials Effects

A 3-year LDRD-ER project to study the response of shocked materials at high pressure and high strain rate has concluded. This project involved a coordinated effort to study single crystal samples that were shock loaded by direct laser irradiation, in-situ and post-recovery measurements, and molecular dynamics and continuum modeling. Laser-based shock experiments have been conducted to study the dynamic response of materials under shock loading materials at a high strain-rate. Experiments were c… more

Date: March 4, 2004

Creator: Kalantar, D. H.; Belak, J.; Bringa, E.; Budil, K.; Colvin, J.; Kumar, M. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Turbulent mix experiments

This report is a reproduction of a set of viewgraphs that describes experimental work done to test mathematical models of turbulent mixing and computer codes for simulating it, to quantify turbulent mix scaling laws.

Date: October 1, 1995

Creator: Dimonte, G.; Schneider, M. & Frerking, E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Turbulent mix experiments and simulations

Hydrodynamic instabilities produce material mixing that can significantly degrade weapons performance. We investigate the Richtmyer-Meshkov (RM) and Rayleigh-Taylor (RT) instabilities in the turbulent regime in two experimental venues. RM experiments are conducted on the Nova laser with strong radiatively driven shocks (Mach > 20) in planar, two fluid targets. Interfacial perturbations are imposed with single sinusoidal modes to test linear theory and with three dimensional (3D) random modes to… more

Date: August 1, 1995

Creator: Dimonte, G.; Schneider, M. & Frerking, C.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department