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, Xrays with small enough bandwidth have become available, allowing the investigation of the lowfrequency 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:
 Univ. of Oxford (United Kingdom). Dept. of Physics
 Univ. of Oxford (United Kingdom). Dept. of Physics; AWE, Reading (United Kingdom)
 SLAC National Accelerator Lab., Menlo Park, CA (United States); Univ. of California, Berkeley, CA (United States). Physics Dept.
 SLAC National Accelerator Lab., Menlo Park, CA (United States)
 HelmholtzZentrum Berlin (HZB), (Germany). Inst. of Radiation Physics
 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) (SC24)
 OSTI Identifier:
 1347922
 Grant/Contract Number:
 AC0276SF00515
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Nature Communications
 Additional Journal Information:
 Journal Volume: 8; Journal ID: ISSN 20411723
 Publisher:
 Nature Publishing Group
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; computational methods; laserproduced 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, Xrays with small enough bandwidth have become available, allowing the investigation of the lowfrequency 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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