A portable X-pinch design for x-ray diagnostics of warm dense matter

TL;DR

This paper presents Dry Pinch I, a portable X-pinch device capable of producing short, intense x-ray bursts suitable for high-energy-density physics diagnostics, with detailed characterization of its emission properties and operational reliability.

Contribution

The paper introduces a novel, portable X-pinch device with detailed analysis of its x-ray emission characteristics and reliable operation at low current rise rates.

Findings

Produces 1.1 ns x-ray bursts with ~50 mJ energy.

Achieves a spatial x-ray hot spot size of ~10 μm in soft x-rays.

Operates reliably at current rise rates below 1 kA/ns.

Abstract

We describe the design and x-ray emission properties (temporal, spatial, and spectral) of Dry Pinch I, a portable X-pinch driver developed at Imperial College London. Dry Pinch I is a direct capacitor discharge device, 300x300x700 mm3 in size and approximately 50 kg in mass, that can be used as an external driver for x-ray diagnostics in high-energy-density physics experiments. Among key findings, the device is shown to reliably produce 1.1 +- 0.3 ns long x-ray bursts that couple approximately 50 mJ of energy into photon energies from 1 to 10 keV. The average shot-to-shot jitter of these bursts is found to be 10 +- 4.6 ns using a combination of x-ray and current diagnostics. The spatial extent of the x-ray hot spot from which the radiation emanates agrees with previously published results for X-pinches suggesting a spot size of 10 +- 6 um in the soft energy region (1-10 keV) and 190 +- 100 um in the hard energy region (>10 keV). These characteristics mean that Dry Pinch I is ideally suited for use as a probe in experiments driven in the laboratory or at external facilities when more conventional sources of probing radiation are not available. At the same time, this is also the first detailed investigation of an X-pinch operating reliably at current rise rates of less than 1 kA/ns.