Beamstop-free small-angle X-ray scattering for multiscale structure measurement of high-energy-density plasma
Year: 2026
Type: article
Abstract: The advent of free-electron lasers has enabled in-situ small-angle X-ray scattering (SAXS) measurements of laser-produced high-energy-density plasma at solid density, with nanometer- and femtosecond-scale resolution. Such plasmas generally exhibit gentle density gradients, which suppress large-angle scattering signals while small-angle scattering components dominate near the direct X-ray beam; the latter signals were hard to access in the conventional SAXS method due to the use of a beamstop. Here, we demonstrate a beamstop-free SAXS system comprising layered metallic filters for optimal attenuation of diffraction signals. It enables continuous acquisition of wide q -range/angular scattering signals with a large dynamic range, including the critical small-angle region containing the direct X-ray beam. This method was applied to a two-dimensional array of submicron columnar plasmas generated by irradiating a high-intensity laser pulse onto an assembly of high-aspect-ratio silicon rods with well-defined sharp edges. We experimentally resolve the microscale and macroscale rarefaction dynamics of bulk electrons driven by the pump-laser pre-pulse and main pulse, revealing the initial plasma scale length as a key parameter governing laser absorption in structured targets. Beamstop-free SAXS enables single-shot multiscale structure measurement and establishes a route toward exploration of stochastic plasma dynamics under high-energy-density conditions, including filamentation instability and turbulence.
Source: Communications Physics
Authors: Masato Ota, Ryutaro Matsui, Melanie Rodel, Shunsuke Egashira, Tomohiro Izumi, Yoshiharu Nakagawa, Yushiro Matsumoto, Otono Kuramoto, Hiroki Ishiara, Kosuke Maeda, Tatiana Pikuz, Alexander Pirozhkov, Alejandro Laso Garcia, Lingen Huang, Alessio Morace, Takumi Minami, Kentaro Sakai, Yuji Fukuyama, Yuto Maeda, Kohei Endo, Soma Nitta, Genki Kamimura, Tomoya Taguchi, Yuki Abe, Hideaki Habara, Hirotaka Nakamura, Bruno Albertazzi, Michel Koenig, Toshinori Yabuuchi, Tadashi Togashi, Yuichi Inubushi, Keiichi Sueda, Kohei Miyanishi, Takeshi Matuoka, Norimasa Ozaki, Naoki Uehara, Yasuhiro Kuramitsu, Keisuke Shigemori, Motoaki Nakatsutsumi, Yuji Fukuda, Hiroshi Sakaguchi, Takumi Yasuda, Kazuhiro Fukami, Thomas E. Cowan, Thomas Kluge, Yasuaki Kishimoto, Youichi Sakawa
Institutions: The Graduate University for Advanced Studies, SOKENDAI, National Institute for Fusion Science, The University of Osaka, Kyoto University, Equilibrium Research, Helmholtz-Zentrum Dresden-Rossendorf, Institute for Laser Technology, National Institutes for Quantum Science and Technology, Kansai Institute for Photon Science, Osaka University of Economics, Osaka City University, Centre National de la Recherche Scientifique, École Polytechnique, Sorbonne Université, Laboratoire pour l'Utilisation des Lasers Intenses, SPring-8, Japan Synchrotron Radiation Research Institute, European X-Ray Free-Electron Laser, Institute of Advanced Energy, Kyoto University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,990
OpenAlex ID: W7222430876