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in creator/contributor: "Derzon, M. S."

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Z-Pinch Driven Inertial Confinement Fusion Target Physics Research at Sandia National Laboratories

Three hohlraum concepts are being pursued at Sandia National Laboratories (SNL) to investigate the possibility of using pulsed power driven magnetic implosions (z-pinches) to drive high gain targets capable of yields in the range of 200-1000 MJ. This research is being conducted on SNL'S.Z facility that is capable of driving peak currents of 20 MA in z-pinch loads producing implosion velocities as high as 7.5X 107 cm/s, x-ray energies approaching 2 MJ, and x-ray powers exceeding 200 TW. This pap… more

Date: October 27, 1998

Creator: Alberts, T. E.; Asay, J. R.; Baca, P. M.; Baker, K. L.; Breeze, S. P.; Chandler, G. A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High Temperature Dynamic Hohlraums on the Pulsed Power Driver Z

In the concept of the dynamic hohlraum an imploding z-pinch is optically thick to its own radiation. Radiation may be trapped inside the pinch to give a radiation temperature inside the pinch greater than that outside the pinch. The radiation is typically produced by colliding an outer Z-pinch liner onto an inner liner. The collision generates a strongly radiating shock, and the radiation is trapped by the outer liner. As the implosion continues after the collision the radiation temperature may… more

Date: January 4, 1999

Creator: Armijo, J.; Chandler, G.A.; Cooper, G.; Derzon, M.S.; Fehl, D.; Gilliland, T. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Z-Pinch Generated X-Rays Demonstrate Indirect-Drive ICF Potential

Hohlraums (measuring 6-mm in diameter by 7-mm in height) have been heated by x-rays from a z-pinch. Over measured x-ray input powers P of 0.7 to 13 TW, the hohlraum radiation temperature T increases from {approximately}55 to {approximately}130 eV, and is in agreement with the Planckian relation P-T{sup 4}. The results suggest that indirect-drive ICF studies involving NIF relevant pulse shapes and <2-mm diameter capsules can he studied using this arrangement.

Date: June 16, 1999

Creator: Bowers, R. L.; Chandler, G. A.; Derzon, M. S.; Hebron, D. E.; Leeper, R. J.; Matzen, M. K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A low jitter, low cost, time-of-flight circuit

A low cost circuit has been developed for use in a neutron time-of-flight spectrometer at the Nova Laser Facility. Using a silicon charged-particle detector, amplifier and constant-fraction discriminator, timing resolution of better than 50 ps FWHM has been achieved. Using an array of many such detectors, very high data rates and precise spectra can be obtained. 3 refs., 2 figs.

Date: October 1, 1987

Creator: Cable, M.D.; Derzon, M.S.; Vieira, R.G. & Spracklen, H.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Light ion sources and target results on PBFA II (Particle Beam Fusion Accelerator II)

Advances in ion beam theory, diagnostics, and experiments in the past two years have enabled efficient generation of intense proton beams on PBFA II, and focusing of the beam power to 5.4 TW/cm{sup 2} on a 6-mm-diameter target. Target experiments have been started with the intense proton beams, since the range of protons at 4--5 MeV is equivalent to that of lithium at 30 MeV. Three series of experiments have been conducted using planar, conical, and cylindrical targets. These tests have provide… more

Date: January 1, 1990

Creator: Cook, D. L.; Bailey, J. E.; Bieg, K. W.; Bloomquist, D. D.; Coats, R. S.; Chandler, G. C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Experimental results and modeling of a dynamic hohlraum on SATURN

Experiments were performed at SATURN, a high current z-pinch, to explore the feasibility of creating a hohlraum by imploding a tungsten wire array onto a low-density foam. Emission measurements in the 200--280 eV energy band were consistent with a 110--135 eV Planckian before the target shock heated, or stagnated, on-axis. Peak pinch radiation temperatures of nominally 160 eV were obtained. Measured early time x-ray emission histories and temperature estimates agree well with modeled performanc… more

Date: June 1, 1998

Creator: Derzon, M. S.; Allshouse, G. O.; Deeney, C.; Leeper, R. J.; Nash, T. J.; Matuska, W. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development and characterization of a time-, position- and energy-resolved x-ray diagnostic for PBFA II target experiments

A time-, position- and energy-resolved soft x-ray (100--500 eV) diagnostic is being developed for PBFA II target experiments. The diagnostic provides measurements of hydrodynamic motion and thermal gradients in light-ion fusion targets. A slit-image of the source is imprinted onto thin sheets (20{mu}m) of organic scintillator to create a one-dimensional image. The scintillator light is then proximity-coupled to a linear array of fiber-optics that transports the light to a streak camera that is … more

Date: December 31, 1992

Creator: Derzon, M. S.; Filuk, A. B.; Pantuso, J.; Dukart, R. J.; Olsen, R.; Barber, T. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Shot-to-shot comparison of the first Li-beam driven hohlraum experiments

Shot-to-shot comparison of the first Li-beam hohlraum experiments on PBFA II provides an opportunity to measure and determine the factors that the affect on-axis reproducibility of the Li ion beam. Both inner shell and thermal x-ray emission are used to estimate the relative beam power on target from shot to shot. The M- and L-shell Au x-ray yield measurements were made with an array of 11 filtered PIN detectors, and the thermal emission measurements were made with an array of three filtered bo… more

Date: August 1, 1994

Creator: Derzon, M. S.; Rochau, G. E.; Chandler, G. A.; Moats, A. R. & Leeper, R. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cylindrical target Li-beam-driven hohlraum experiments

The authors performed a series of experiments on the Particle Beam Fusion Accelerator II (PBFA II) in May, 1994, and obtained a brightness temperature of 61 {+-} 2 eV for an ion-beam heated hohlraum. The hohlraum was a 4-mm-diameter, right-circular cylinder with a 1.5-mm-thick gold wall, a low-density CH foam fill, and a 1.5- or 3-mm-diameter diagnostic aperture in the top. The nominal parameters of the radially-incident PBFA II Li ion beam were 9 MeV peak energy ({approximately}10 MeV at the g… more

Date: June 1, 1998

Creator: Derzon, M.S.; Aubert, J. & Chandler, G.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High-pressure /sup 3/He gas scintillation neutron spectrometer

A high-pressure, /sup 3/He-Xe gas scintillation spectrometer has been developed for neutron spectroscopy on D-D fusion plasmas. The spectrometer exhibits an energy resolution of (121 +- 20 keV) keV (FWHM) at 2.5 MeV and an efficiency of (1.9 +- 0.4) x 10/sup -3/ (n/cm/sup 2/)/sup -1/. The contribution to the resolution (FWHM) from counting statistics is only (22 +- 3 keV) and the remainder is due predominantly to the variation of light collection efficiency with location of neutron events withi… more

Date: October 1, 1985

Creator: Derzon, M.S.; Slaughter, D.R. & Prussin, S.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of emission diameter as a function of time on foam z- pinch plasmas

We have developed a streaked imaging capability to make time-resolved measurements of the emission size for low density foam z-pinches. By lens coupling visible emission from the z-pinch target to an array of fiber optics we obtained the emission profile in the visible as a function of time with radial resolution of 300 {mu}m. To measure the emission at temperatures greater than {approx}40 eV the source was slit-imaged or pin-hole imaged onto an x-ray filtered scintillator. Non-uniformities in … more

Date: May 14, 1996

Creator: Lazier, S. E.; Barber, T. L.; Derzon, M. S. & Kellogg, J. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Target diagnostic system for the National Ignition Facility (NIF)

A review of recent progress on the design of a diagnostic system proposed for ignition target experiments on the National Ignition Facility (NIF) will be presented. This diagnostic package contains an extensive suite of optical, x-ray, gamma-ray, and neutron diagnostics that enable measurements of the performance of both direct and indirect driven NIF targets. The philosophy used in designing all of the diagnostics in the set has emphasized redundant and independent measurement of fundamental p… more

Date: July 1, 1996

Creator: Leeper, R.J.; Chandler, G.A.; Cooper, G.W. & Derzon, M.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

On the transparency of foam in low-density foam Z-pinch experiments

Foam Z-pinch experiments have been performed on the SATURN and Z machines at Sandia National Laboratories to study physics issues related to x-ray radiation generation and inertial confinement fusion. A significant issue for foam Z-pinch experiments is the transparency of the heated foam as a function of time and wavelength. Foam transparency will be important in future foam Z-pinch experiments both because it influences the time-dependent radiation field seen by an ICF capsule embedded in the … more

Date: December 31, 1998

Creator: MacFarlane, J. J.; Derzon, M. S.; Nash, T. J.; Chandler, G. A. & Peterson, D. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

PBFA II lithium beam characterization from inner-shell x-ray images

The Particle Beam Fusion Accelerator (PBFA II) is not driving targets with ICF-relevant lithium ion beams. During the most recent lithium beam target series, time-integrated x-ray pinhole cameras viewed the ion-induced inner-shell x-ray fluorescence from the central gold cone target and a titanium-coated strip. Ion beam profiles at a nominal 10 mm radius and fixed azimuthal direction were obtained from images of the Ti K{sub {alpha}}, fluorescence of a Ti-coated Al diagnostic wire. The gold con… more

Date: May 1, 1994

Creator: Moats, A. R.; Derzon, M. S.; Chandler, G. A.; Dukart, R. J. & Haill, T. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of a visible framing camera diagnostic for the study of current initiation in z-pinch plasmas

The authors assembled and tested a visible framing camera system to take 5 ns FWHM images of the early time emission from a z-pinch plasma. This diagnostic was used in conjunction with a visible streak camera allowing early time emissions measurements to diagnose current initiation. Individual frames from gated image intensifiers were proximity coupled to charge injection device (CID) cameras and read out at video rate and 8-bit resolution. A mirror was used to view the pinch from a 90-degree a… more

Date: July 1, 1996

Creator: Muron, D. J.; Hurst, M. J. & Derzon, M. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Spectroscopic diagnosis of foam z-pinch plasmas on SATURN

Solid and annular silicon aerogel and agar foams were shot on the accelerator SATURN to study plasma initiation, acceleration, and stagnation. SATURN delivers 7 MA with a 50 nsec rise time to these foam loads. We fielded several spectroscopic diagnostics to measure plasma parameters throughout the z-pinch discharge. A spatially resolved single frame time-gated EUV spectrometer measured the extent of plasma ablation off the surface foam. A time integrated crystal spectrometer showed that charact… more

Date: June 1996

Creator: Nash, T. J.; Derzon, M. S.; Allshouse, G.; Deeney, C.; Jobe, D.; McGurn, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dynamic hohlraum experiments on SATURN

The authors have imploded a 17.5 mm diameter 120-tungsten-wire array weighing 450 {mu}g/cm onto a 4 mm diameter silicon aerogel foam weighing 650 {mu}g/cm, using the pulsed power driver SATURN. A peak current of 7.0 MA drives a 48 ns implosion to strike time followed by 8 ns of foam compression until stagnation. The tungsten strikes the foam with a 50 cm/{mu}s implosion velocity. Radiation temperatures were measured from the side and along the axis with filtered x-ray diode arrays. There is evi… more

Date: August 1, 1997

Creator: Nash, T.J.; Derzon, M.S. & Allshouse, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Axial diagnostic package for Z

The authors have developed and fielded an axial diagnostic package for the 20 MA, 100 ns, z-pinch driver Z. The package is used to diagnose dynamic hohlraum experiments which require an axial line of sight. The heart of the package is a reentrant cone originally used to diagnose ion-beam-driven hohlraums on PBFA-H. It has one diagnostic line of sight at 0 degrees, 4 at 6 degrees, and 4 at 9 degrees. In addition it has a number of viewing, alignment, and vacuum feedthrough ports. The front of th… more

Date: June 1, 1998

Creator: Nash, T.J.; Derzon, M.S. & Chandler, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Application of 2-D Simulations to Z-Pinch Experiment Design and Analysis

The successful 2-D simulations of z-pinch experiments (reproducing such features as the measured experimental current drive, radiation pulse shape, peak power and total radiated energy) can lead to a better understanding of the underlying physics in z-pinch implosions and to the opportunity to use such simulations in the analysis of experimental data and in the design of new experiments. Such use has been made with LANL simulations of experiments on the Sandia Saturn and Z accelerators. Applica… more

Date: October 19, 1998

Creator: Peterson, D. L.; Bowers, R. L.; Matuska, W.; Chandler, G. A.; Deeney, C.; Derzon, M. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Modeling a 1-D bremsstrahlung and neutron imaging array for use on Sandia`s Z machine

Inertial confinement fusion is being studied on the Z facility at Sandia National Laboratories. Z is a large z-pinch machine which can provide 20 MA of current to z-pinch loads producing {approximately}1.8 MJ of soft x-rays in less than 10 ns. Within the pinch region, decelerated electrons produce a strong source of bremsstrahlung radiation which varies from shot to shot. Additionally, a variety of ICF targets produce fusion neutrons whose intensity and distribution depend on the temperature an… more

Date: June 1, 1998

Creator: Rochau, G.A.; Derzon, M.S.; Fehl, D.; Rochau, G.E.; Lazier, S. & Droemer, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The physics of fast Z pinches

The spectacular progress made during the last few years in reaching high energy densities in fast implosions of annular current sheaths (fast Z pinches) opens new possibilities for a broad spectrum of experiments, from x-ray generation to controlled thermonuclear fusion and astrophysics. Presently Z pinches are the most intense laboratory X ray sources (1.8 MJ in 5 ns from a volume 2 mm in diameter and 2 cm tall). Powers in excess of 200 TW have been obtained. This warrants summarizes the prese… more

Date: July 1, 1998

Creator: Ryutov, D. D.; Derzon, M. S. & Matzen, M. K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Ion beam generation and focusing on PBFA (Particle Beam Fusion Accelerator) II

During the past year we have succeeded in obtaining a 5 TW/cm{sup 2} proton focus on Sandia National Laboratories' Particle Beam Fusion Accelerator (PBFA) II. This has allowed us to shift our experimental emphasis to the implementation of an improved ion diode geometry for higher voltage operation, full azimuthal beam characterization, and especially lithium ion source experiments. We have made significant progress in each of these areas during the past year, demonstrating 10 MV diode operation… more

Date: January 1, 1990

Creator: Stinnett, R. W.; Bailey, J. E.; Bieg, K. W.; Coats, R. S.; Chandler, G.; Derzon, M. S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department