1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Demonstrated transparent mode in nested wire arrays used for dynamic hohlraum Z pinches
Rent:
Rent this article for
USD
10.1063/1.2730488
/content/aip/journal/pop/14/5/10.1063/1.2730488
http://aip.metastore.ingenta.com/content/aip/journal/pop/14/5/10.1063/1.2730488
View: Figures

Figures

Image of FIG. 1.
FIG. 1.

(Color) (A1) Experimental arrangement showing position of target T, inner I, and outer O arrays, and top radiation exit hole REH, together with the general diagnostic layout. (A2) On axis radial apertures viewing target T, target plus pedestal , pedestal P only, and the off-axis aperture that views the O/I collision and rear wall . (B1) Wire configuration for baseline geometry. (B2) Wire configuration for reversed-mass geometry. IWG refers to the inner-wire-gap spacing and to the diameter of the given wire.

Image of FIG. 2.
FIG. 2.

(Color) Calculated outer and inner radii for baseline configuration from the thin-shell dynamics model assuming O/I collision is (A) hydrodynamic and (B) transparent. Calculated outer and inner radii for reversed-mass configuration assuming O/I collision is (C) hydrodynamic and (D) transparent.

Image of FIG. 3.
FIG. 3.

(Color) Resistive-MHD simulation of (A) baseline, and (B) reverse-mass configuration showing evolution of the mass density in a radial-azimuthal wedge.

Image of FIG. 4.
FIG. 4.

(Color) TGS waveforms are shown for successive shots on Z. The viewing location of the detector is indicated on the CAD drawing of the wire array hardware, part D. The edge of the outer array is indicated by a red dashed line. The TGS detector observes the diagnostic slot outside the outer array on shot Z1244, between the outer and inner arrays on shot Z1245 and at the inner array on shot Z1246. A burst of radiation observed near the inner array (red circle) is observed at the time the outer and inner array interact.

Image of FIG. 5.
FIG. 5.

(Color) Measured (blue) and calculated (red) (using the thin-shell dynamics model) load current for (A) baseline and (B) reverse-mass configurations.

Image of FIG. 6.
FIG. 6.

(Color) Normalized radial x-ray power pulse shapes from resistive-MHD simulations of baseline (red) and reverse-mass (blue) cases.

Image of FIG. 7.
FIG. 7.

(Color) Resistive-MHD simulation of (A) baseline and (B) reverse-mass mass density showing evolution of the mass density like that shown in Fig. 3, but now distinguishing plasma generated from the outer and inner arrays. Times correspond to those identified in Fig. 6.

Image of FIG. 8.
FIG. 8.

(Color) Resistive-MHD simulation of (A) baseline and (B) reverse-mass radial mass densities as a function of times identified in Fig. 6.

Image of FIG. 9.
FIG. 9.

(Color) Resistive-MHD simulation of (A) baseline and (B) reverse-mass azimuthal mass-density profiles of the outer and inner arrays at peak radial power, as identified in Fig. 6.

Image of FIG. 10.
FIG. 10.

(Color) Resistive-MHD simulation of (A) baseline and (C) reverse-mass radial x-ray powers. Measured radial x-ray powers for (B) baseline and (D) reverse-mass configurations. The measurements have been geometrically corrected for the limited viewing aperture. In (A) and (C), the bottom arrows refer to the timing of the outer-array inner-array (O/I), the outer-array target (O/T), the inner-array target collision, and final stagnation (S) calculated assuming transparency in the thin-shell model, relative to the O/I timing.

Image of FIG. 11.
FIG. 11.

(Color) Measured on-axis (red) and off-axis (purple) radial x-ray powers for (A) baseline and (B) reverse-mass configurations. Shown are the expected timings from the thin-shell dynamics model assuming the O/I collision is transparent (at the bottom of each figure) and hydrodynamic (at the top of each figure).

Image of FIG. 12.
FIG. 12.

(Color) Measured radial (on axis in red) and axial x-ray powers (blue and green) for (A) reversed-mass and (B) baseline configurations. Timing marks at the bottom of each figure refer to those calculated from the analytic model relative to the O/I time.

Image of FIG. 13.
FIG. 13.

(Color) Measured and calculated time difference (A) between the O/I and O/T collisions, and (B) between the O/I and S (stagnation) as a function of the calculated momentum transfer fraction, , for the reverse-mass configuration.

Image of FIG. 14.
FIG. 14.

(Color) Measured and calculated time difference (A) between the O/I and O/T collisions, and (B) between the O/I and S (stagnation) as a function of the calculated momentum transfer fraction, , for the baseline configuration.

Image of FIG. 15.
FIG. 15.

(Color) This self-emission image of shot Z1246 was taken before peak pinch. The superimposed red curve represents the relative mass density distribution derived from the TGS x-ray detectors as described in Sec. V B. The green lines show the starting radii of the inner and outer wire arrays. The blue line indicates the effective radius of the current as derived from electrical measurements assuming an inductive cylinder at the time of the image. The dashed magenta lines indicate the average position of the leading bubbles and trailing spikes as estimated from the self-emission image.

Image of FIG. 16.
FIG. 16.

(Color) Measured and radiation-MHD simulated MRT wavelength, assuming a hydrodyamic collision mode.

Image of FIG. 17.
FIG. 17.

(Color) Measured off-axis radial x-ray power and average current radius and velocity for (A) baseline and (B) reverse-mass configurations. Timing marks at the bottom of each figure refer to times measured experimentally. Shown in (A) are the positions of the leading and trailing edges of the MRT instability like those shown in Fig. 15.

Image of FIG. 18.
FIG. 18.

(Color) Sequence of times in the plane showing the outer plasma (idealized as a sheet of thickness interacting. At (A) the inner wire encounters the outer plasma sheet causing a bow shock to occur. This is developed by (B) when the inner wire encounters the skin layer in which large electric fields are present driving a fast rising current in the inner wire and its ablating plasma, and (C) at time the outer plasma is moving past the almost stationary inner wire. The current has transferred to the inner wire, and the outer plasma has closed current loops of dimension half the inner wire gap size; these loops decay on a time scale, and there is almost no net current in the outer plasma as it reaches the axis.

Loading

Article metrics loading...

/content/aip/journal/pop/14/5/10.1063/1.2730488
2007-05-14
2014-04-24
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Demonstrated transparent mode in nested wire arrays used for dynamic hohlraum Z pinches
http://aip.metastore.ingenta.com/content/aip/journal/pop/14/5/10.1063/1.2730488
10.1063/1.2730488
SEARCH_EXPAND_ITEM