Pulsed Power Plasmas

 Introduction

 Pulsed Power Drivers

 X-pinches

 Wire arrays

 Pulsed Power ICF

 Laboratory Astrophysics

X-Pinches

X-pinch plasmas are of great interest due to their exotic high energy density properties. They are formed from two or more wires mounted parallel between two electrodes, which are then rotated relative to each other until the wires touch [1]. Wires are typically 5 - 25 microns in diameter, and materials such as alumimium, molybdemun, copper, steel and tungsten are commonly employed.

A fast-rising current is then applied which generates a plasma. This plasma is compressed where the global magnetic field is strongest, at the cross point, causing a short, high flux x-ray yield. This rapid plasma compression has been studied in detail using radiography and time-resolved spectroscopy ([2] and references therein), which determined plasma conditions to be T_e ~ 1 keV, n_e ~10²³ cm^-3 (~solid density) [3]. This hot-spot is also compact and highly transient, and the x-ray source size is typically ~1 micron with a duration of < 1 ns. This led to the use of x-pinches as a high resolution x-ray backlighter for various experiments [4-6].

In addition, a low density coronal plasma is created around each wire which is accelerated to the global axis, forming a zippered plasma column which propagates out of the upper electrode late in time. These jets are of interest for laboratory astrophysics applications

[1] S.M. Zakharov et al Sov. Tech. Phys. Lett., 8 (9), pp. 456-457 (1982).
[2] T. A. Shelkovenkoet al, Phys. Plasmas, 8, 1305 (2001)
[3] Shelkovenko T A et al, Phys. Plasmas, 9, 2165 (2002)
[4] Shelkovenko T A et al, Rev. Sci. Instrum., 72, p667 (2001)
[5] T. A. Shelkovenko et al, Phys Plasmas, 14, p102702 (2007)
[6] F. N. Beg, R. B. Stephens et al, Appl. Phys. Lett. 89, 101502 (2006)