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.
Study of the effect of current rise time on the formation of the precursor column in cylindrical wire array Z pinches at 1 MA
Rent this article for


Image of FIG. 1.
FIG. 1.

Variation of the ion line density at the array axis with time for MAGPIE and COBRA. Horizontal line indicates critical ion line density for precursor column formation, and vertical lines indicate precursor formation times for MAGPIE (measured) and COBRA (predicted).

Image of FIG. 2.
FIG. 2.

Current pulses for MAGPIE and COBRA, along with running integral of the square of the current pulse.

Image of FIG. 3.
FIG. 3.

Sequence of gated self-emission images for W loads in COBRA showing formation dynamics of the precursor column.

Image of FIG. 4.
FIG. 4.

Lineouts across Al and W arrays at 100 and 104 ns, respectively, showing broad early time emission profiles.

Image of FIG. 5.
FIG. 5.

Correlation of the peak in the radiation signature to the observation of the precursor column on the optical streak images for a W array on COBRA.

Image of FIG. 6.
FIG. 6.

Variation of emission diameter during column formation for Al array on COBRA.

Image of FIG. 7.
FIG. 7.

Plot of diameter variation of precursor column during formation for (left) Al and (right) W arrays on both MAGPIE and COBRA using axes normalized to the time of formation and minimum diameters in each case (put Al/W labels on plots).

Image of FIG. 8.
FIG. 8.

Laser shadowograms of W arrays from (left) COBRA at 150 ns and (right) MAGPIE at 160 ns showing formation of the precursor column initially at the anode in both cases.

Image of FIG. 9.
FIG. 9.

Streak image and magnification of a W load on COBRA showing plasma structure around precursor column formation time.

Image of FIG. 10.
FIG. 10.

Radiographs with areal density lineouts for (upper) W (150 ns) and (lower) Al (130 ns) arrays on COBRA.

Image of FIG. 11.
FIG. 11.

plots of the precursor column mass density as a function of time compared to the rocket model.

Image of FIG. 12.
FIG. 12.

Radiograph and lineouts of W axial flares on COBRA (0.5 mm from wire position).

Image of FIG. 13.
FIG. 13.

(Top) XUV spectra from Al arrays on (upper) COBRA (time integrated) and (lower) MAGPIE [time gated at precursor column formation (Ref. 54)], with (bottom) spectral lineouts of each.

Image of FIG. 14.
FIG. 14.

Variation in precursor column formation time with ablation velocity assumed for COBRA current drive. Dotted line indicates giving formation time of 107 ns.

Image of FIG. 15.
FIG. 15.

Full array with radiographs along with magnified sections indicated by black box of (a) side on large Al wire cores (COBRA, 120ns, 110% rise time), (b) rear of same on MAGPIE (197 ns, 79% rise time), and (c) typical small Al wire radiograph from MAGPIE (220ns, 88% rise time).

Image of FIG. 16.
FIG. 16.

Plots of axial density variation as a function of array radius calculated from a two-velocity rocket model (see text) for (left) 8 mm radius array on MAGPIE at 160 ns, and (right) 10 mm radius array on Z at 100 ns.


Generic image for table
Table I.

Summary of precursor column characteristic on MAGPIE and COBRA along with analytical predictions for COBRA.


Article metrics loading...


Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Study of the effect of current rise time on the formation of the precursor column in cylindrical wire array Z pinches at 1 MA