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Chapman DA, Vorberger J, Fletcher LB, Baggott RA, Divol L, Döppner T, Falcone RW, Glenzer SH, Gregori G, Guymer TM, Kritcher AL, Landen OL, Ma T, Pak AE, Gericke DO. Observation of finite-wavelength screening in high-energy-density matter. Nat Commun 2015; 6:6839. [PMID: 25904218 PMCID: PMC4423234 DOI: 10.1038/ncomms7839] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 02/26/2015] [Indexed: 11/10/2022] Open
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.
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Affiliation(s)
- D. A. Chapman
- AWE plc, Radiation Physics Department, Aldermaston, Reading RG7 4PR, UK
- Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - J. Vorberger
- Max-Planck-Institut für die Physik komplexer Systeme, Dresden 01187, Germany
| | - L. B. Fletcher
- High-Energy-Density Science Division, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - R. A. Baggott
- Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - L. Divol
- National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - T. Döppner
- National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R. W. Falcone
- Physics Department, University of California, Berkeley, California 94720, USA
| | - S. H. Glenzer
- High-Energy-Density Science Division, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - G. Gregori
- Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK
| | - T. M. Guymer
- AWE plc, Radiation Physics Department, Aldermaston, Reading RG7 4PR, UK
| | - A. L. Kritcher
- National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - O. L. Landen
- National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - T. Ma
- National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A. E. Pak
- National Ignition Facility and Photon Science Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D. O. Gericke
- Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL, UK
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Kugland NL, Gregori G, Bandyopadhyay S, Brenner CM, Brown CRD, Constantin C, Glenzer SH, Khattak FY, Kritcher AL, Niemann C, Otten A, Pasley J, Pelka A, Roth M, Spindloe C, Riley D. Evolution of elastic x-ray scattering in laser-shocked warm dense lithium. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:066406. [PMID: 20365285 DOI: 10.1103/physreve.80.066406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Indexed: 05/29/2023]
Abstract
We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4-ns-long laser pulses. Separate 1-ns-long laser pulses were used to generate a bright source of 2.96 keV Cl Ly- alpha photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120 degrees using a highly oriented pyrolytic graphite crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation-hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state Z[over ] and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.
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Affiliation(s)
- N L Kugland
- Physics Department, University of California-Los Angeles, Los Angeles, California 90095, USA
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Potekhin AY, Massacrier G, Chabrier G. Equation of state for partially ionized carbon at high temperatures. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 72:046402. [PMID: 16383540 DOI: 10.1103/physreve.72.046402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2004] [Revised: 08/08/2005] [Indexed: 05/05/2023]
Abstract
Equation of state for partially ionized carbon at temperatures T approximately > or = 10(5) K is calculated in a wide range of densities, using the method of free energy minimization in the framework of the chemical picture of plasmas. The free energy model includes the internal partition functions of bound species. The latter are calculated by a self-consistent treatment of each ionization stage in the plasma environment taking into account pressure ionization. The long-range Coulomb interactions between ions and screening of the ions by free electrons are included using our previously published analytical model.
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