Development of Talbot-Lau interferometry for the study of laser generated HED plasmas at SACLA XFEL *

Talbot interferometers are well known systems originally developed in synchrotron facilities for medical purposes. When set up in Moiré configuration, the advantage of these grating-based interferometers lies in their ability to furnish multiple sets of data in a single probing in a single shot. The on-detector mean illumination gives the X-ray attenuation and is equivalent to classical radiography. Additionally, the interference pattern provides a phase image of the probed medium thereby giving a direct measure of its refraction and electron density gradients. Finally, scattering can be captured through dark-field imaging. Recently, this technique has been adapted to investigate high-energy-density physics (HEDP) at laser facilities. This talk will present the continuation of this diagnostic’s development on XFEL facilities, examining the evolution of laser-generated dense plasmas obtained at the BL3, EH5 end station at SACLA XFEL. These plasmas were formed when a metallic foil was ablated by a 5 ns laser pulse with intensities of . The dynamics of this system were captured using a Talbot-Lau interferometer designed for use with the facility’s monochromatic X-ray probe to observe the evolution of the rear foil’s surface. The output interferograms were then post-processed to retrieve attenuation, phase, and dark-field images of the generated plasma. The resulting images accurately captured the plasma and scattering profiles, establishing the viability of this technique and paving the way for future HEDP studies on XFEL facilities.