title: Observation of finite-wavelength screening in high-energy-density matter.
abstract: A key component for the description of charged particle systems is the screening of the Coulomb interaction between charge carriers. First investigated in the 1920s by Debye and Hückel for electrolytes, charge screening is important for determining the structural and transport properties of matter as diverse as astrophysical and laboratory plasmas, nuclear matter such as quark-gluon plasmas, electrons in solids, planetary cores and charged macromolecules. For systems with negligible dynamics, screening is still mostly described using a Debye-Hückel-type approach. Here, we report the novel observation of a significant departure from the Debye-Hückel-type model in high-energy-density matter by probing laser-driven, shock-compressed plastic with high-energy X-rays. We use spectrally resolved X-ray scattering in a geometry that enables direct investigation of the screening cloud, and demonstrate that the observed elastic scattering amplitude is only well described within a more general approach.
authors.affiliation: 1] AWE plc, Radiation Physics Department, Aldermaston, Reading RG7 4PR, UK [2] Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
authors.forename: D A
authors.initials: DA
authors.lastname: Chapman
authors.affiliation: Max-Planck-Institut für die Physik komplexer Systeme, Dresden 01187, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Vorberger
authors.affiliation: High-Energy-Density Science Division, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Fletcher
authors.affiliation: Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
authors.forename: R A
authors.initials: RA
authors.lastname: Baggott
authors.affiliation: National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: L
authors.initials: L
authors.lastname: Divol
authors.affiliation: National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: T
authors.initials: T
authors.lastname: Döppner
authors.affiliation: Physics Department, University of California, Berkeley, California 94720, USA.
authors.forename: R W
authors.initials: RW
authors.lastname: Falcone
authors.affiliation: High-Energy-Density Science Division, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Glenzer
authors.affiliation: Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK.
authors.forename: G
authors.initials: G
authors.lastname: Gregori
authors.affiliation: AWE plc, Radiation Physics Department, Aldermaston, Reading RG7 4PR, UK.
authors.forename: T M
authors.initials: TM
authors.lastname: Guymer
authors.affiliation: National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: A L
authors.initials: AL
authors.lastname: Kritcher
authors.affiliation: National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: O L
authors.initials: OL
authors.lastname: Landen
authors.affiliation: National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: T
authors.initials: T
authors.lastname: Ma
authors.affiliation: National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: Pak
authors.affiliation: Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL, UK.
authors.forename: D O
authors.initials: DO
authors.lastname: Gericke