The X pinch as a point source for point-projection x-ray radiography

Point-projection radiography of dense plasmas and other objects using an X pinch as the x-ray source is discussed. An X pinch, generated using two or more wires that cross and touch, in the form of an X, as the load of a pulsed power generator, reliably produces a small, bright x-ray radiation source very near the original cross point of the wires. Taking advantage of the small source size (in some cases <2 µm at energies above a few keV), radiographs of objects can be obtained without using pinholes. In addition, the short x-ray emission duration (<20 ps in some cases for energies above a few keV) of the X pinch radiation enables sharp radiographs of rapidly changing dense plasmas. Detailed measurements of the emission characteristics of X pinches made using different wire materials and in different energy ranges using a set of x-ray diagnostics with high temporal and spatial resolution are presented. A comparison of the radiated energy and the imaging properties of two and up to seven wire X pinches are discussed. The application of the X pinch x-ray source for phase-contrast x-ray radiography of low absorption objects is demonstrated.