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Title: A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics

Abstract

We determined the state and evolution of planets, brown dwarfs and neutron star crusts by the properties of dense and compressed matter. Furthermore, due to the inherent difficulties in modelling strongly coupled plasmas, however, current predictions of transport coefficients differ by orders of magnitude. Collective modes are a prominent feature, whose spectra may serve as an important tool to validate theoretical predictions for dense matter. With recent advances in free electron laser technology, X-rays with small enough bandwidth have become available, allowing the investigation of the low-frequency ion modes in dense matter. Here, we present numerical predictions for these ion modes and demonstrate significant changes to their strength and dispersion if dissipative processes are included by Langevin dynamics. Notably, a strong diffusive mode around zero frequency arises, which is not present, or much weaker, in standard simulations. These results have profound consequences in the interpretation of transport coefficients in dense plasmas.

Authors:
 [1];  [2];  [1];  [3];  [4];  [5];  [5];  [6];  [1]
  1. Univ. of Oxford (United Kingdom). Dept. of Physics
  2. Univ. of Oxford (United Kingdom). Dept. of Physics; AWE, Reading (United Kingdom)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States); Univ. of California, Berkeley, CA (United States). Physics Dept.
  4. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  5. Helmholtz-Zentrum Berlin (HZB), (Germany). Inst. of Radiation Physics
  6. Univ. of Warwick, Coventry (United Kingdom). Centre for Fusion, Space and Astrophysics
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1347922
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; computational methods; laser-produced plasmas

Citation Formats

Mabey, P., Richardson, S., White, T. G., Fletcher, L. B., Glenzer, S. H., Hartley, N. J., Vorberger, J., Gericke, D. O., and Gregori, G. A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics. United States: N. p., 2017. Web. doi:10.1038/ncomms14125.
Mabey, P., Richardson, S., White, T. G., Fletcher, L. B., Glenzer, S. H., Hartley, N. J., Vorberger, J., Gericke, D. O., & Gregori, G. A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics. United States. doi:10.1038/ncomms14125.
Mabey, P., Richardson, S., White, T. G., Fletcher, L. B., Glenzer, S. H., Hartley, N. J., Vorberger, J., Gericke, D. O., and Gregori, G. Mon . "A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics". United States. doi:10.1038/ncomms14125. https://www.osti.gov/servlets/purl/1347922.
@article{osti_1347922,
title = {A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics},
author = {Mabey, P. and Richardson, S. and White, T. G. and Fletcher, L. B. and Glenzer, S. H. and Hartley, N. J. and Vorberger, J. and Gericke, D. O. and Gregori, G.},
abstractNote = {We determined the state and evolution of planets, brown dwarfs and neutron star crusts by the properties of dense and compressed matter. Furthermore, due to the inherent difficulties in modelling strongly coupled plasmas, however, current predictions of transport coefficients differ by orders of magnitude. Collective modes are a prominent feature, whose spectra may serve as an important tool to validate theoretical predictions for dense matter. With recent advances in free electron laser technology, X-rays with small enough bandwidth have become available, allowing the investigation of the low-frequency ion modes in dense matter. Here, we present numerical predictions for these ion modes and demonstrate significant changes to their strength and dispersion if dissipative processes are included by Langevin dynamics. Notably, a strong diffusive mode around zero frequency arises, which is not present, or much weaker, in standard simulations. These results have profound consequences in the interpretation of transport coefficients in dense plasmas.},
doi = {10.1038/ncomms14125},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Mon Jan 30 00:00:00 EST 2017},
month = {Mon Jan 30 00:00:00 EST 2017}
}

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Free Publicly Available Full Text
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Cited by: 3works
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