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C.A. Coverdale, P.D. LePell,
C. Deeney,
D.E. Beutler,
S.C. Jones,
G. Chantler,
J. Greenwoll,
J.P. Chittenden,
T. Bateson,
K.J. Dudley,
M.E. Cuneo
[show abstract]
[hide abstract]
ABSTRACT: Z -pinch experiments at pulsed-power facilities generally field a wide range of diagnostics, designed to make measurements and study the relevant physics during all phases of the Z -pinch. Optical and X-ray images are collected to study ablation, implosion, and the stagnated pinch; yield and power measurements are made at various photon energies; and time-integrated and time-resolved spectroscopies are recorded to infer plasma conditions before, during, and after stagnation. Typically, diagnostics fielded are dispersed azimuthally around the Z -pinch and at varying distances relative to the Z -pinch. The data are then analyzed and interpreted as a single entity to provide detailed information about a particular process or physics effect. Correlation of the results of the individual diagnostics in this fashion assumes that each diagnostic would measure the same result regardless of its azimuthal or radial location. Assessments of diagnostics to measure K-shell yield at the Z accelerator, which are fielded at varying azimuthal locations and radial distances, are presented. These measurements illustrate that the K-shell emission is azimuthally uniform for titanium, stainless-steel, and copper wire arrays and that the standard correction for radial distance is valid. The importance of view-factor corrections is also discussed.
IEEE Transactions on Plasma Science 05/2010; · 1.17 Impact Factor
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B Jones,
C Deeney,
J L McKenney,
D J Ampleford,
C A Coverdale, P D Lepell,
K P Shelton,
A S Safronova,
V L Kantsyrev,
G Osborne,
V I Sotnikov,
V V Ivanov,
D Fedin,
V Nalajala,
F Yilmaz,
I Shrestha
[show abstract]
[hide abstract]
ABSTRACT: Axially localized NaF dopants are coated onto Al cylindrical wire arrays in order to act as spectroscopic tracers in the stagnated z-pinch plasma. Non-local-thermodynamic-equilibrium kinetic models fit to Na K-shell lines provide an independent measurement of the density and temperature that is consistent with spectroscopic analysis of K-shell emissions from Al and an alloyed Mg dopant. Axial transport of the Na dopant is observed, enabling quantitative study of instabilities in dense z-pinch plasmas.
Physical Review Letters 04/2008; 100(10):105003. · 7.37 Impact Factor
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A. S. Safronova,
V. L. Kantsyrev,
A. A. Esaulov,
N. D. Ouart,
M. F. Yilmaz,
K. M. Williamson,
I. Shrestha,
G. C. Osborne,
J. B. Greenly,
K. M. Chandler,
R. D. McBride,
D. A. Chalenski,
D. A. Hammer,
B. R. Kusse, P. D. LePell
[show abstract]
[hide abstract]
ABSTRACT: Low wire number nested array Z-pinch experiments have been carried out with wires made of aluminum, stainless steel (uniform), and combinations of these two materials (mixed) on the 1 MA COBRA generator at Cornell University [
J. D. Douglass, J. B. Greenly, D. A. Hammer et al., in Proceedings of the 15th IEEE International Pulsed Power Conference (IEEE, Piscataway, NJ, 2005)
]. The outer array consisted of eight wires, whereas the inner array had four or eight wires. The 10 μm Al wires were alloy 5056 and the 6.25 μm stainless steel wires were alloy SS304. The diagnostic suite included fast-x-ray and extreme ultraviolet (EUV) detectors, a time-gated x-ray pinhole camera, x-ray spectrometers, and laser shadow imaging. The main focus was made on the spectroscopic study of plasma evolution after the main x-ray burst though the data from photoconducting detector (PCD) and EUV signals over the whole period of current, and in addition laser shadowgraphy images before the main x-ray burst were analyzed. Modeling of the time-gated spectra recorded after the main x-ray burst indicates that the electron temperature Te either follows the PCD signals and peaks at times of the second (and the third if present) x-ray burst or has the higher value at the first frame (closest to the main x-ray burst), then slightly changes and increases at the last frame, which coincides with the second maximum of the current. It was also found that the values of Te never drop below 150 eV, and the EUV signal remains intense even when the PCD signal is almost zero.
Physics of Plasmas 03/2008; 15(3):033302-033302-14. · 2.15 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The Z machine at Sandia National Laboratories drives 20 MA in 100 ns through a cylindrical array of fine wires which implodes due to the strong j × B force, generating up to 250 TW of soft x‐ray radiation when the z‐pinch plasma stagnates on axis. The copious broadband self‐emission makes the dynamics of the implosion well suited to diagnosis with soft x‐ray imaging and spectroscopy. A monochromatic self‐emission imaging instrument has recently been developed on Z which reflects pinhole images from a multilayer mirror onto a 1 ns gated microchannel plate detector. The multilayer can be designed to provide narrowband (∼10 eV) reflection in the 100–700 eV photon energy range, allowing observation of the soft emission from accreting mass as it assembles into a hot, dense plasma column on the array axis. In the present instrument configuration, data at 277 eV photon energy have been obtained for plasmas ranging from Al to W, and the z‐pinch implosion and stagnation will be discussed along with > 1 keV self‐emission imaging and spectroscopy. Collisional‐radiative simulations are currently being pursued in order to link the imaged emissivity to plasma temperature and density profiles and address the role of opacity in interpreting the data. © 2007 American Institute of Physics
AIP Conference Proceedings. 08/2007; 926(1):229-237.
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C.A. Coverdale,
C. Deeney,
B. Jones, P.D. LePell,
A.L. Velikovich,
J.W. Thornhill,
J. Davis,
Y.K. Chong,
R.W. Clark,
J.P. Apruzese,
K.G. Whitney,
J. Chittenden
[show abstract]
[hide abstract]
ABSTRACT: A variety of wire array experiments the last few years at the 20 MA Z Accelerator have been performed to assess the impact of initial load mass, initial load diameter, and variations of the nested array configuration on the K-shell output. Nominally, optimized configurations have been identified, with optimization determined by the highest K-shell output with the fastest rising, narrowest x-ray pulse. In this paper, the results of experiments performed to evaluate additional load configuration variations such as increased radial anode-cathode (RAK) gap, increases in wire number on nested arrays, and orientation of the nested arrays are presented. For stainless steel wire arrays (K-shell emission ∼6.7 keV), increasing the wire number on the nested arrays resulted in increased K-shell yield and K-shell power. Increasing the RAK gap from 6 mm to 10 mm resulted in changes to both the soft x-ray emission and stainless steel K-shell emission. The orientation of the wires on the inner and outer arrays of copper (8.4 keV) wire arrays was not observed to impact the radiated output, although calculations suggest that the effect of wire orientation will be overwhelmed by magnetic field asymmetries induced by the wire location relative to the openings in the return current can.
Pulsed Power Conference, 2007 16th IEEE International; 07/2007
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C. A. Coverdale,
C. Deeney,
A. L. Velikovich,
J. Davis,
R. W. Clark,
Y. K. Chong,
J. Chittenden,
S. Chantrenne,
C. L. Ruiz,
G. W. Cooper,
A. J. Nelson,
J. Franklin, P. D. LePell,
J. P. Apruzese,
J. Levine,
J. Banister
[show abstract]
[hide abstract]
ABSTRACT: Experiments on the Z accelerator with deuterium gas-puff implosions have produced up to 3.7×1013 (±20%) neutrons at 2.34 MeV (±0.10 MeV). Although the mechanism for generating these neutrons was not definitively identified, this neutron output is 100 times more than previously observed from neutron-producing experiments at Z. Dopant gases in the deuterium (argon and chlorine) were used to study implosion characteristics and stagnated plasma conditions through x-ray yield measurements and spectroscopy. Magnetohydrodynamic (MHD) calculations have suggested that the dopants improved the neutron output through better plasma compression, which has been studied in experiments increasing the dopant fraction. Scaling these experiments, and additional MHD calculations, suggest that ∼ 5×1014 deuterium-deuterium (DD) neutrons could be generated at the 26-MA refurbished Z facility.
Physics of Plasmas 04/2007; 14(5):056309-056309-7. · 2.15 Impact Factor
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C. A. Coverdale,
C. Deeney,
A. L. Velikovich,
R. W. Clark,
Y. K. Chong,
J. Davis,
J. Chittenden,
C. L. Ruiz,
G. W. Cooper,
A. J. Nelson, [......], P. D. LePell,
J. P. Apruzese,
J. Levine,
J. Banister,
N. Qi,
Plasma Physics Division, Naval Research Lab, Washington, D.C,
Blackett Laboratories, Imperial College, London,
Sandia National Laboratories, Albuquerque, New Mexico,
Ktech Corporation, Albuquerque, New Mexico,
Communications/Pulse Sciences Division, San Leandro, CA
[show abstract]
[hide abstract]
ABSTRACT: Experiments on the Z accelerator with deuterium gas puff implosions have produced up to 3.9x10{sup 13} ({+-}20%) neutrons at 2.34 MeV ({+-}0.10 MeV). Experimentally, the mechanism for generating these neutrons has not been definitively identified through isotropy measurements, but activation diagnostics suggest multiple mechanisms may be responsible. One-, two-, and three-dimensional magnetohydrodynamic (MHD) calculations have indicated that thermonuclear outputs from Z could be expected to be in the (0.3-1.0)x10{sup 14} range. X-ray diagnostics of plasma conditions, fielded to look at dopant materials in the deuterium, have shown that the stagnated deuterium plasma achieved electron temperatures of 2.2 keV and ion densities of 2x10{sup 20} cm{sup -3}, in agreement with the MHD calculations.
Physics of Plasmas 02/2007; 14(2). · 2.15 Impact Factor
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C.A. Coverdale,
C. Deeney,
B Jones, P.D. LePell,
A.L. Velikovich,
J.W. Thornhill,
J.P. Apruzese,
K.G. Whitney,
R.W. Clark,
J Davis,
J.S. Levine,
H.M. Sze,
J.W. Banister,
B.H. Failor,
N. Qi,
Y. Maron
[show abstract]
[hide abstract]
ABSTRACT: Over the last several years, the Z Accelerator has been engaged in research on near-Planckian x-ray sources for inertial confinement fusion and on K-shell emitting sources for radiation-material interaction studies. These radiating z pinches exhibit complex dynamics that have been, and continue to be, studied over a wide range of configurations. In this paper, the progress to date for the production of tens to hundreds of kilojoules of K-shell emission from 8 keV to 3 keV will be presented. Nested wire arrays and multi-shell gas puffs have been employed to help mitigate implosion instabilities and asymmetries to produce x-ray powers of tens of terawatts with emitted x-ray risetimes of a few nanoseconds. Spectroscopy and modeling of these pinches are providing insight into the role of temperature and density gradients and other plasma phenomena in the production of the radiation. Future directions will also be discussed.
Magagauss Magnetic Field Generation and Related Topics, 2006 IEEE International Conference on; 12/2006
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V. SOTNIKOV ,
V. V. IVANOV ,
T. E. COWAN ,
J. N. LEBOEUF ,
B. V. OLIVER ,
C. COVERDALE ,
B. JONES ,
C. DEENEY ,
T. A. MEHLHORN , P. D. LePELL ,
P. HELLINGER ,
P. TRÁVNÍCEK
[show abstract]
[hide abstract]
ABSTRACT: Three-dimensional hybrid simulation of a plasma current-carrying column reveal two different regimes of sausage and kink instability development. In the first regime, with small Hall parameter, development of instabilities leads to the appearance of large-scale axial perturbations and eventually to bending of the plasma column. In the second regime, with a four-times-larger Hall parameter, small-scale perturbations dominate and no bending of the plasma column is observed. Simulation results are compared with laser probing experimental data obtained during wire array implosions on the Zebra pulse power generator at the Nevada Terawatt Facility.
Journal of Plasma Physics 11/2006; 72(06):1113 - 1116. · 0.94 Impact Factor
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J.W. Thornhill,
A.L. Velikovich,
R.W. Clark,
J.P. Apruzese,
J. Davis,
K.G. Whitney,
P.L. Coleman,
C.A. Coverdale,
C. Deeney,
B.M. Jones, P.D. LePell
[show abstract]
[hide abstract]
ABSTRACT: This paper presents theoretical extrapolations for the multi-keV X-ray radiation production capability of the 26-MA ZR accelerator at Sandia National Laboratories, which is scheduled to become available for experiments in 2007. These extrapolations are based on scaling models and ideas that have been developed over the years. These models and ideas have evolved and been refined through the process of benchmarking one-dimensional nonlocal-thermodynamic equilibrium magnetohydrodynamic model results to experimental K-shell yields and powers as well as inferred temperatures and densities. For this ZR assessment, the models are first benchmarked to K-shell yields obtained from argon, titanium, stainless-steel, and copper Z experiments and then they are applied to extrapolate yield predictions to the ZR machine. Extrapolations are based on 2-cm-length loads and similar wire configurations and nozzle designs as those employed in Z experiments. Projected K-shell yields for Ar (photon energy ~3 keV), Ti (~5 keV), stainless steel (~7 keV), and Cu (~8.6 keV) are 520, 300, 200, and 80 kJ, respectively. In addition, the high-energy free-bound continuum emission above 10 keV is calculated to be 40 kJ on ZR
IEEE Transactions on Plasma Science 11/2006; · 1.17 Impact Factor
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V.V. Ivanov,
G.S. Sarkisov,
P.J. Laca,
V.I. Sotnikov,
V.L. Kantsyrev,
B.M. Jones,
C.A. Coverdale, P.D. LePell,
C. Deeney,
K.W. Struve,
A.L. Astanovitskiy,
D.A. Fedin,
B. Le Galloudec,
V. Nalajala,
I. Shrestha,
T.E. Cowan
[show abstract]
[hide abstract]
ABSTRACT: A Faraday rotation diagnostic was applied for the investigation of magnetic fields in plasma of 1-MA wire arrays and X-pinches. Laser-probing diagnostics at the Zebra generator include a four-channel polarointerferometer and a four-frame shadowgraphy. The Faraday rotation diagnostic consists of shadow and Faraday channels, shearing air-wedge interferometer, and an additional schlieren channel. The implosion dynamics of the wire arrays were studied. A current in the plasma column of Al low-wire number arrays was found by the Faraday rotation diagnostic. Optical diagnostics showed a turbulent plasma and bubblelike objects in the plasma column of Al wire arrays. The Faraday rotation diagnostic demonstrated a complicated structure of magnetic fields in X-pinch plasma
IEEE Transactions on Plasma Science 11/2006; · 1.17 Impact Factor
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V.I. Sotnikov,
V.V. Ivanov,
T.E. Cowan,
J.-N.G. Leboeuf,
B.V. Oliver,
C.A. Coverdale,
B.M. Jones,
C. Deeney,
T.A. Mehlhorn,
G.S. Sarkisov, P.D. LePell
[show abstract]
[hide abstract]
ABSTRACT: Recent experiments (laser multiframe shadowgraphy and Faraday rotation diagnostics) with Al imploding wire arrays in the 1-MA "Zebra" accelerator at the Nevada Terawatt Facility have demonstrated that a significant amount of current is going through the central region of the high-beta precursor plasma. With time, the perturbations develop both long scale structures and short-wavelength oscillations in the directions perpendicular to the magnetic field. The most likely candidate for the observed phenomena is the flutelike electromagnetic modes. These are excited in the current-carrying high-beta inhomogeneous precursor plasma due to the curvature of the magnetic field produced by the current. These modes may also play a role in the stagnation phase of Z-pinches. In this paper, nonlinear equations describing electromagnetic-flute-type oscillations in the high-beta precursor plasma are derived, and the linear stage of instability of these waves is examined. A comparison with the experimental results is performed as well
IEEE Transactions on Plasma Science 11/2006; · 1.17 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: A time-resolved, monochromatic soft x-ray diagnostic has been developed for self-emission imaging of imploding z pinches on the Z accelerator [R. B. Spielman etal, Phys. Plasmas 5, 2105 (1998)] at Sandia National Laboratories. Multiple pinhole images are reflected from a planar multilayer mirror with narrow photon energy bandwidth (≪10 eV ) onto a 1 ns gated microchannel plate detector. High-energy bremsstrahlung x rays are not reflected, providing improved signal to noise in comparison to a standard filtered pinhole camera included in the same beamline of the instrument. An example of data from the existing ∼277 eV imaging system is presented, showing cooler imploding mass extending to larger radius than the on-axis K -shell emission of an aluminum wire array. Multilayer mirror and filter pair configurations ranging from 96 to 769 eV are discussed.
Review of Scientific Instruments 11/2006; · 1.37 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Summary form only given. Tests of nested aluminum (A15056) arrays at the Z accelerator have produced X-ray outputs of >350 kJ. The measured X-rays consist of the K-shell emission of aluminum and magnesium ions, stripped to the He- and H-like states, as well as free-bound continuum. For these tests we recorded these emissions with a variety of spectrometers: time-integrated, spatially resolved and time-resolved, spatially integrated spectrometers. These instruments were configured to capture the broad range of K-shell emissions from the plasma ions and as such were survey instruments, with spectral resolutions of approximately 300 (E/DeltaE). In this paper, details of the two Z shots, Z1519 and Z1520, will be presented. For these shots, each spectrometer showed intense Mg K-shell lines as well as intense Al K-shell lines; however, the intensity of the Mg lines exceeds the 5% Mg mass content of the 5056 alloy. In particular, the ratio of the Mg and Al Lyman-alpha lines approaches 25% (Mg/Al), suggestive of substantial line opacity. The time-resolved measurements show that the most intense lines (Al Lyman-alpha) persist for the camera's entire detection time of 21 ns, exceeding that of the lower energy Al He-alpha line. Furthermore, the Al Lyman-alpha lines extend out to a radius of 4-5 mm, and uniformly emit along the plasma's visible length; these observations are consistent with pinhole imaging data collected on the same shots. Measurements of the X-ray yields and pulse shapes will also be presented
Plasma Science, 2006. ICOPS 2006. IEEE Conference Record - Abstracts. The 33rd IEEE International Conference on; 07/2006
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[show abstract]
[hide abstract]
ABSTRACT: A monochromatic X-ray self-emission imaging diagnostic has been developed for the Z accelerator, which drives 20 MA in 100 ns to implode wire array Z-pinches, generating up to 250 TW of soft X-ray radiation. This instrument reflects eight pinhole images from a flat Cr/C multilayer mirror (MLM) onto a 1-ns time-resolved microchannel plate detector. The MLM reflects 277-eV photons with ∼5-eV bandwidth and 20% peak reflectivity, and an aluminized parylene filter shields the detector from visible light. High-energy bremsstrahlung X-rays do not follow the reflected beam path, and so the background on the shielded detector is reduced compared to a standard pinhole camera. The MLM-reflected images offer low-photon-energy spectral resolution that filtration alone cannot, yielding high-quality images of the final stages of the Z-pinch implosion. Initial data on Z from a Cu wire array will be presented. Observed phenomena include implosion instabilities, zippered implosion of a piston onto a precursor column during the onset of stagnation, accretion of trailing colder mass during the X-ray pulse, and cathode reemission. The inferred implosion velocity is significantly less than thin-shell implosion model calculations, and well below what is required for efficient Cu K-shell radiation. Instability-dominated, bright-spot Cu K-shell emission is seen on a second adjacent eight-frame filtered pinhole camera that is in the same beamline.
IEEE Transactions on Plasma Science 05/2006; · 1.17 Impact Factor
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V.L. Kantsyrev,
A.S. Safronova,
D.A. Fedin,
V.V. Ivanov,
A.A. Esaulov,
V. Nalajala,
I. Shrestha,
S. Pokala,
K. Williamson,
N.D. Ouart,
M.F. Yilmaz,
P. Laca,
T.E. Cowan,
L.I. Rudakov,
B. Jones,
C.A. Coverdale,
C. Deeney, P.D. LePell,
A.L. Velikovich,
A.S. Chuvatin
[show abstract]
[hide abstract]
ABSTRACT: In the following experiments, we studied implosions of different wire arrays and X-pinches produced on the 1-MA Zebra generator at the University of Nevada, Reno. Diagnostics included both spatially-resolved and time-gated X-ray imaging and spectroscopy, and laser probing. In particular, we compared planar wire arrays, to which little energy could be coupled via the conventional magnetic-to-kinetic conversion mechanism, to cylindrical wire arrays of comparable dimensions and mass. The planar wire arrays were shown to radiate much higher peak power and more energy in subkiloelectronvolt and kiloelectronvolt spectral ranges than cylindrical wire arrays. We tested the theoretical conjecture that enhanced resistivity due to the small-scale inhomogeneity of wire-array plasmas has a major effect on dynamics, energy coupling and radiation performance of wire-array Z-pinches. The study of Al, Alumel, and W cylindrical wire arrays shows a wide variety of characteristic behaviors in plasma implosions discussed hereinafter. Additional experimental results for symmetric and asymmetric, uniform stainless steel, Cu, Mo, combined Al/Mo, Mo/Al, Al/W, W/Al, and Mo/W X-pinches are also presented. New data for the total radiation yield are obtained. The planar structures of X-pinch plasma and the corresponding electron beam was observed for most of X-pinches. The generation of hot spots along original wires positions-cooler than those from the cross-wire region-and arc structures with hot spots between wires were found for X-pinches composed from Al, Cu, and W wires.
IEEE Transactions on Plasma Science 05/2006; · 1.17 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Pulsed power driven metallic wire-array Z pinches are the most powerful and efficient laboratory x-ray sources. Furthermore, under certain conditions the soft x-ray energy radiated in a 5 ns pulse at stagnation can exceed the estimated kinetic energy of the radial implosion phase by a factor of 3 to 4. A theoretical model is developed here to explain this, allowing the rapid conversion of magnetic energy to a very high ion temperature plasma through the generation of fine scale, fast-growing m = 0 interchange MHD instabilities at stagnation. These saturate nonlinearly and provide associated ion viscous heating. Next the ion energy is transferred by equipartition to the electrons and thus to soft x-ray radiation. Recent time-resolved iron spectra at Sandia confirm an ion temperature Ti of over 200 keV (2 x 10(9) degrees), as predicted by theory. These are believed to be record temperatures for a magnetically confined plasma.
Physical Review Letters 03/2006; 96(7):075003. · 7.37 Impact Factor
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V.V. Ivanov,
V. L. Kantsyrev,
V. I. Sotnikov,
D. A. Fedin,
A. L. Astanovitskiy,
B. Le Galloudec,
V. Nalajala,
I. Shrestha,
T. E. Cowan,
B. Jones,
C.A. Coverdale,
C. Deeney, P.D. LePell
[show abstract]
[hide abstract]
ABSTRACT: Implosion of wire arrays was investigated at the 1-MA Zebra accelerator by multi-frame laser probing and gated x-ray self-emission diagnostics. Different regimes of implosion were observed in Al and Cu wire arrays. Implosion of Al loads with mass 33-37 µg/cm produces a dense pinch 1-1.5 mm in diameter. Strong instabilities are observed in the z-pinch at the time of stagnation. Implosion of “over-massed” loads produces a plasma column 3-4 mm in diameter with a core. The plasma column does not collapse during the x-ray pulse. The core of the plasma column is not subjected to the kink instability and transforms to a chain of dense spots in the later stage. Different regimes of implosion were observed in Al 8 x 15 µm loads presumably due to variations in the current pulse and load conditions. Observed regimes are compared to 3D hybrid simulation of ideal and non-ideal magnetohydrodynamics modes of implosion.
Physics of Plasmas 01/2006; 13(1):012704. · 2.15 Impact Factor
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V. V. Ivanov,
V. L. Kantsyrev,
V. I. Sotnikov,
D. A. Fedin,
A. L. Astanovitskiy,
B. Le Galloudec,
V. Nalajala,
I. Shrestha,
T. E. Cowan,
B. Jones,
C. A. Coverdale,
C. Deeney, P. D. LePell
[show abstract]
[hide abstract]
ABSTRACT: Implosion of wire arrays was investigated at the 1 MA Zebra accelerator by multiframe laser probing and gated x-ray self-emission diagnostics. Different regimes of implosion were observed in Al and Cu wire arrays. Implosion of Al loads with masses of 33–37 μg/cm produces a dense pinch 1–1.5 mm in diameter. Strong instabilities are observed in the Z pinch at the time of stagnation. Implosion of “overmassed” loads produces a plasma column 3–4 mm in diameter with a core. The plasma column does not collapse during the x-ray pulse. The core of the plasma column is not subjected to the kink instability and transforms to a chain of dense spots in the later stage. Different regimes of implosion were observed in Al 8×15 μm loads presumably due to variations in the current pulse and load conditions. Observed regimes are compared to three-dimensional hybrid simulation of ideal and nonideal magnetohydrodynamics modes of implosion.
Physics of Plasmas 01/2006; 13(1):012704-012704-8. · 2.15 Impact Factor
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D. J. Ampleford,
S. V. Lebedev,
J. P. Chittenden,
S. N. Bland,
S. C. Bott,
G. N. Hall,
J. B. A. Palmer,
J. Rapley,
V. L. Kantsyrev,
A. S. Safronova, [......],
V. I. Sotnikov,
F. Yilmaz,
N. Ouart,
V. Nalajala,
I. Shrestha,
S. Pokala,
B. Jones,
C. Deeney,
C. A. Coverdale, P. D. LePell
[show abstract]
[hide abstract]
ABSTRACT: We present initial results from imploding conical wire array experiments performed on both the MAGPIE generator (1MA, 240ns) at Imperial College London and the Nevada Terawatt Facility’s Zebra generator (1MA, 100ns) at University of Nevada, Reno. This paper will discuss the implosion dynamics of conical wire arrays, including initial implosion of the cathode end of the array and the formation of a magnetic bubble. © 2006 American Institute of Physics
AIP Conference Proceedings. 01/2006; 808(1):33-36.
