A5071356090- Pulsed Power Technology Applications
- Particle accelerators and beam dynamics
- Gyrotron and Vacuum Electronics Research
- Laser-Plasma Interactions and Diagnostics
- Electrostatic Discharge in Electronics
- Particle Accelerators and Free-Electron Lasers
- Plasma Diagnostics and Applications
- Electromagnetic Launch and Propulsion Technology
- Magnetic confinement fusion research
- Nuclear Physics and Applications
- Ion-surface interactions and analysis
- Laser-induced spectroscopy and plasma
- Integrated Circuits and Semiconductor Failure Analysis
- Radiation Effects and Dosimetry
- Fusion materials and technologies
- High-pressure geophysics and materials
- Electron and X-Ray Spectroscopy Techniques
- Superconducting Materials and Applications
- Laser Design and Applications
- Atomic and Molecular Physics
- Magnetic Field Sensors Techniques
- X-ray Spectroscopy and Fluorescence Analysis
- Astro and Planetary Science
- Laser-Matter Interactions and Applications
- Particle Detector Development and Performance
Sandia National Laboratories California
2009-2024
Sandia National Laboratories
2013-2023
Weizmann Institute of Science
2018
University of Michigan
2018
National Security Technologies (United States)
2014
Yamagata University
2014
Radiology Associates of Albuquerque
1986-2010
Institute for High Energy Physics
2007
Office of Scientific and Technical Information
2006
National Technical Information Service
2006
The Z accelerator [R. B. Spielman, W. A. Stygar, J. F. Seamen et al., Proceedings of the 11th International Pulsed Power Conference, Baltimore, MD, 1997, edited by G. Cooperstein and I. Vitkovitsky (IEEE, Piscataway, NJ, 1997), Vol. 1, p. 709] at Sandia National Laboratories delivers ∼20MA load currents to create high magnetic fields (>1000T) pressures (megabar gigabar). In a z-pinch configuration, pressure (the Lorentz force) supersonically implodes plasma created from cylindrical...
We have developed an accelerator architecture that can serve as the basis of design petawatt-class $z$-pinch drivers. The has been applied to two accelerators, each which be contained within a 104-m-diameter cylindrical tank. One is driven by slow ($\ensuremath{\sim}1\text{ }\ensuremath{\mu}\mathrm{s}$) Marx generators, are mature technology but necessitate significant pulse compression achieve short pulses ($\ensuremath{\ll}1\text{ required drive $z$ pinches. other powered linear...
In this article we present the design and test results of most powerful, fast linear transformer driver (LTD) stage developed to date. This 1-MA LTD consists 40 parallel RLC (resistor R, inductor L, capacitor C) circuits called ``bricks'' that are triggered simultaneously; it is able deliver $\ensuremath{\sim}1\text{ }\text{ }\mathrm{MA}$ current pulse with a rise time $\ensuremath{\sim}100\text{ }\mathrm{ns}$ into $\ensuremath{\sim}0.1\mathrm{\text{\ensuremath{-}}}\mathrm{Ohm}$ matched...
We have developed conceptual designs of two petawatt-class pulsed-power accelerators: Z 300 and 800. The are based on an accelerator architecture that is founded concepts: single-stage electrical-pulse compression impedance matching [Phys. Rev. ST Accel. Beams 10, 030401 (2007)]. prime power source each machine consists 90 linear-transformer-driver (LTD) modules. Each module comprises LTD cavities connected electrically in series, which powered by 5-GW bricks parallel. (A brick a single...
The nuclear reactions $^{12}\mathrm{C}(^{12}\mathrm{C}, \ensuremath{\alpha})^{20}\mathrm{Ne}$ and p)^{23}\mathrm{Na}$ have been observed from 5-MeV down to 2.45-MeV center-of-mass energy. Angular distributions energy of the protons $\ensuremath{\alpha}$ particles were analyzed obtain total cross sections other information. Coulomb angular momentum barrier penetrability was factored out elucidate intermediate resonance structure in factor $\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{S}$. rise...
High current pulsed-power generators efficiently store and deliver magnetic energy to z-pinch targets. We review applications of magnetically driven implosions (MDIs) inertial confinement fusion. Previous research on MDIs wire-array z-pinches for radiation-driven indirect-drive target designs is summarized. Indirect-drive are compared with new targets that imploded by direct application pressure produced the pulse. describe design elements such as larger absorbed energy, magnetized...
Most of the modern high-current high-voltage pulsed power generators require several stages pulse conditioning (pulse forming) to convert multimicrosecond pulses Marx generator output 40-300-ns required by a number applications including X-ray radiography, linear accelerators, <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</i> -pinch, isentropic compression, and inertial fusion energy drivers. This makes devices large, cumbersome operate,...
The linear transformer driver (LTD) is a new method for constructing high current, high-voltage pulsed accelerators. salient feature of the approach switching and inductively adding pulses at low voltage straight out capacitors through inductance transfer soft iron core isolation. Sandia National Laboratories are actively pursuing development class accelerator based on LTD technology. Presently, current experimental research concentrated two aspects: first, to study repetition rate...
We have developed two new gas switches that are designed to be used with linear transformer drivers. The switches, which can DC charged 200 kV and triggered less than a 2-ns $1\mathrm{\text{\ensuremath{-}}}\ensuremath{\sigma}$ jitter, overall inductances ranging from 69 85 nH. When transferring 400 J of energy per shot, the lifetimes in excess 5000 shots. insulated 130--270 PSIA air submerged oil during operation. These should allow development drivers more compact higher peak power.
We are investigating several alternate gas-switch designs for use in linear transformer drivers. To meet linear-transformer-driver (LTD) requirements, these air-insulated switches must be DC charged to 200 kV, triggerable with a jitter of 5 ns or less, have very low prefire and no-fire rates ($\ensuremath{\sim}1$ ${10}^{4}$ shots), lifetime at least thousand shots. Since the switch inductance plays significant role limiting rise time peak current LTD circuit, needs as possible. The required...
The objectives of this tutorial are as follows: 1) to help students and researchers develop a basic understanding how pulsed-power systems used create high-energy-density (HED) matter; 2) new, compact, efficient technology called linear transformer drivers (LTDs); 3) understand why LTDs an attractive for driving HED physics (HEDP) experiments; 4) contrast with the more traditional Marx-generator/pulse-forming-line approach HEDP 5) briefly review history LTD well some LTD-driven research...
We have measured the x-ray power and energy radiated by a tungsten-wire-array z pinch as function of peak current width anode-cathode gap at base pinch. The measurements were performed 13- 19-MA currents 1-, 2-, 3-, 4-mm gaps. wire material, number wires, wire-array diameter, length, wire-array-electrode design, normalized-pinch-current time history, implosion time, diagnostic package held constant for experiments. To keep constant, mass array was increased I2 (i.e., diameter each I), where...
We present the first comprehensive study of high wire-number, wire-array $Z$-pinch dynamics at 14--18 MA using x-ray backlighting and optical shadowgraphy diagnostics. The cylindrical arrays retain slowly expanding, dense wire cores initial position up to 60% total implosion time. Azimuthally correlated instabilities array edge appear during this stage which continue grow in amplitude wavelength after start bulk motion, resulting measurable trailing mass that does not arrive on axis before...
Wire-array z pinches show promise as a high-power, efficient, reproducible, and low-cost x-ray source for high-yield indirect-drive inertial confinement fusion. Recently, rapid progress has been made in our understanding of the implosion dynamics compact (20-mm-diam), high-current (11–19MA), single nested wire arrays. As at lower currents (1–3MA), array (and both outer inner system), variety effects that arise from initially discrete nature wires: long ablation phase 50%-80% current pulse...
AbstractThe long-range goal of the Z-Pinch IFE program is to produce an economically-attractive power plant using high-yield z-pinch-driven targets (~3GJ) with low rep-rate per chamber (~0.1 Hz). The present mainline choice for a uses LTD (Linear Transformer Driver) repetitive pulsed driver, Recyclable Transmission Line (RTL), dynamic hohlraum target, and thick-liquid wall chamber. RTL connects driver directly made from frozen coolant or material that easily separable (such as carbon steel)....
We demonstrate that a wide variety of current-pulse shapes can be generated using linear-transformer-driver (LTD) module drives an internal water-insulated transmission line. The are produced by varying the timing and initial charge voltage each module's cavities. LTD-driven accelerator architecture outlined in [Phys. Rev. ST Accel. Beams 10, 030401 (2007)] provides additional pulse-shaping flexibility allowing modules drive to triggered at different times. output pulses would combined...
We are performing experiments with a 92-kV, 810-kA, 74.6-GW linear transformer driver (LTD) cavity. This cavity generates $\ensuremath{\sim}100\text{ }\text{ }\mathrm{ns}$ power pulse from DC-charged capacitors in single step. Our start an existing 100-kV, 490-kA LTD and making number of improvements to it that aimed at increasing the cavity's peak output better understanding its operation. gas switches, capacitors, magnetic toroids as well heavily instrumenting These have increased current...
The mass distribution and axial instability growth of wire-array Z-pinch implosions driven by 14–20 MA has been studied using high-resolution, monochromatic x-ray backlighting diagnostics. A delayed implosion is consistently observed in which persistent, dense wire cores continuously ablate plasma until they dissipate the main begins. In arrays with small interwire gaps, azimuthally correlated instabilities appear during ablation stage subsequently seed early magneto-Rayleigh–Taylor...
We have developed wire-array z -pinch scaling relations for plasma-physics and inertial-confinement-fusion (ICF) experiments. The can be applied to the design of accelerators high-fusion-yield (approximately 0.4 GJ/shot) inertial-fusion-energy 3 research. find that (delta(a)/delta(RT)) proportional (m/l)1/4 (Rgamma)(-1/2), where delta(a) is imploding-sheath thickness a wire-ablation-dominated pinch, delta(RT) sheath Rayleigh-Taylor-dominated m total mass, l axial length array, R initial...
Researchers at The University of Michigan have constructed and tested a 1‐MA Linear Transformer Driver (LTD), the first its type to reach USA. Accelerator for Inductive Z‐pinch Experiments, (MAIZE), is based on LTD developed Institute High Current Electronics in collaboration with Sandia National Labs UM. This utilizes 80 capacitors 40 spark gap switches, arranged "bricks," deliver 1 MA, 100 kV pulse ns risetime into matched resistive load. Preliminary resistive‐load test results are...
In linear transformer drivers [Phys. Rev. ST Accel. Beams 12, 050402 (2009); Phys. 050401 (2009)] as well any other induction accelerator cavities, ferromagnetic cores are used to prevent the current from flowing along cavity walls which in parallel with load. But if core is made of conductive material, applied voltage pulse generates eddy itself heats and therefore also reduces overall driver (LTD) efficiency. The energy loss due generation depends on specific resistivity design core,...
We have conceived a new class of prime-power sources for pulsed-power accelerators: impedance-matched Marx generators (IMGs). The fundamental building block an IMG is brick, which consists two capacitors connected electrically in series with single switch. An comprises stage or several stages distributed axially and series. Each powered by brick bricks azimuthally within the parallel. multistage drive coaxial transmission line conical center conductor. When are triggered sequentially to...
In this paper, we present the most recent test of multigap gas switches which are one key elements fast LTD stages with oil insulation [1, 2]. Inside these switches, charge voltage is distributed between multiple gaps use a corona discharge [3]. The evident advantages technique low cost and extreme compactness divider because it just consists few needles that soldered to switch electrodes. At same time, for proper operation switch, special features have be taken into account. These include...
Experiments have been performed on a nominal 100 ns rise time, MegaAmpere (MA)-class linear transformer driver to explore the magneto-Rayleigh-Taylor (MRT) instability in planar geometry. Plasma loads consisted of ablated 400 nm-thick, 1 cm-wide aluminum foils located between two parallel-plate return-current electrodes. acceleration was adjusted by offsetting position foil (cathode) anode plates. Diagnostics included double-pulse, sub-ns laser shadowgraphy, and machine current B-dot loops....
It is well established that pulsed power technology relatively cheaper than other architectures aiming to produce high-current, high-voltage electron or ion accelerators. The footprints of most accelerators are large, making them incompatible for applications require either portability a large number similar components very high devices (like Z-pinch accelerators). Most the modern several stages pulse conditioning (pulse forming) convert multimicrosecond Marx generator output 50-100 ns...