Development of an energy-dispersive X-ray absorption fine structure spectroscopy diagnostic driven by a portable X-pinch backlighter*

We present progress in the campaign to develop energy-dispersive X-ray absorption fine structure (EDXAFS) diagnostic driven by a small portable X-pinch.

EDXAFS allows simultaneous measurement of density and temperature, as well as the electronic and geometric structure of dense samples. These measurements are applicable to optically opaque states of matter produced in dynamic compression and current heating experiments. Dry Pinch I, a portable X-pinch developed at Imperial College to connect to external experiments, can produce on-sample photon flux of >3000 photons / eV around the Aluminium K edge within a single ~1 ns long X-ray burst when fielded in a dispersive geometry. The on-sample flux is comparable to well established EDXAFS beamlines such as the ID24 at the European Research Synchrotron Facility. The crystal geometry enables a spectral bandwidth of 100 eV around the Aluminium K edge at 1559 eV (sufficient for near-edge structure measurements) or 400 eV around the Titanium K edge at 4996 eV (sufficient for extended structure measurements). The absorption spectra of these elements are currently being measured for solid-state foils and pending successful results will move towards probing of dielectrically tamped current-exploded foils.