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DOE OSTI · 2572070

Model-free Rayleigh weight from x-ray Thomson scattering measurements

Dornheim, Tobias [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000172936615)·Bellenbaum, Hannah M. [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany] (ORCID:0009000665301017)·Bethkenhagen, Mandy [Centre National de la Recherche Scientifique (CNRS) (France); Sorbonne Univ., Paris (France); Ecole Polytechnique, Palaiseau (France)] (ORCID:0000000218382129)·Hansen, Stephanie B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000218869770)·Böhme, Maximilian P. [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000302903628)·Döppner, Tilo [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000257037125)·Fletcher, Luke B. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000271207194)·Gawne, Thomas [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000199983606)·Gericke, Dirk O. [Univ. of Warwick, Coventry (United Kingdom)] (ORCID:0000000167979004)·Hamel, Sebastien [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000342460892)·Kraus, Dominik [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Univ. of Rostock (Germany)] (ORCID:0000000263504180)·MacDonald, Mike J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000262956978)·Moldabekov, Zhandos A. [Center for Advanced Systems Understanding (CASUS), Görlitz (Germany); Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000297259208)·Preston, T. R. [European XFEL, Schenefeld (Germany)] (ORCID:0000000312282263)·Redmer, R. [Univ. of Rostock (Germany)] (ORCID:000000033440863X)·Schörner, Maximilian [Univ. of Rostock (Germany)] (ORCID:0000000179258917)·Schwalbe, Sebastian [Center for Advanced Systems Understanding (CASUS), Görlitz (Germany); Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000245610158)·Tolias, Panagiotis [KTH Royal Inst. of Technology, Stockholm (Sweden)] (ORCID:0000000196328104)·Vorberger, Jan [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000159269192)

Abstract

X-ray Thomson scattering (XRTS) has emerged as a powerful tool for the diagnostics of matter under extreme conditions. In principle, it gives one access to important system parameters such as the temperature, density, and ionization state, but the interpretation of the measured XRTS intensity usually relies on theoretical models and approximations. In this context, a key property is given by the Rayleigh weight that describes the electronic localization around the ions. Here, we show that it is possible to extract the Rayleigh weight directly from the experimental data without the need for any model calculations or simulations. As a practical application, we consider an experimental measurement of strongly compressed Be at the National Ignition Facility [Döppner et al., Nature 618, 270–275 (2023)]. We demonstrate that experimental results for the Rayleigh weight open up new avenues for the interpretation of XRTS experiments by matching the measurement with ab initio simulations such as density functional theory or path integral Monte Carlo. Interestingly, this new procedure leads to significantly lower density compared to previously used chemical models.

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BibTeXRIS

Dornheim, Tobias [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000172936615), Bellenbaum, Hannah M. [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany] (ORCID:0009000665301017), Bethkenhagen, Mandy [Centre National de la Recherche Scientifique (CNRS) (France); Sorbonne Univ., Paris (France); Ecole Polytechnique, Palaiseau (France)] (ORCID:0000000218382129), Hansen, Stephanie B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000218869770), Böhme, Maximilian P. [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000302903628), Döppner, Tilo [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000257037125), Fletcher, Luke B. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000271207194), Gawne, Thomas [Center for Advanced Systems Understanding (CASUS), Görlitz, Germany; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000199983606), Gericke, Dirk O. [Univ. of Warwick, Coventry (United Kingdom)] (ORCID:0000000167979004), Hamel, Sebastien [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000342460892), Kraus, Dominik [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Univ. of Rostock (Germany)] (ORCID:0000000263504180), MacDonald, Mike J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000262956978), Moldabekov, Zhandos A. [Center for Advanced Systems Understanding (CASUS), Görlitz (Germany); Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000297259208), Preston, T. R. [European XFEL, Schenefeld (Germany)] (ORCID:0000000312282263), Redmer, R. [Univ. of Rostock (Germany)] (ORCID:000000033440863X), Schörner, Maximilian [Univ. of Rostock (Germany)] (ORCID:0000000179258917), Schwalbe, Sebastian [Center for Advanced Systems Understanding (CASUS), Görlitz (Germany); Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000245610158), Tolias, Panagiotis [KTH Royal Inst. of Technology, Stockholm (Sweden)] (ORCID:0000000196328104), Vorberger, Jan [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany)] (ORCID:0000000159269192). 2025-05-23. Model-free Rayleigh weight from x-ray Thomson scattering measurements. https://doi.org/10.1063/5.0238630

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