skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: ELECTRON-ION SCATTERING IN DENSE MULTI-COMPONENT PLASMAS: APPLICATION TO THE OUTER CRUST OF AN ACCRETING NEUTRON STAR

Abstract

The thermal conductivity of a dense multi-component plasma (MCP) is critical to the modeling of accreting neutron stars. To this end, we perform large-scale molecular dynamics simulations to calculate the static structure factor of the dense MCP in the neutron star crust from near the photosphere-ocean boundary to the vicinity of the neutron drip point. The structure factors are used to validate a microscopic linear mixing rule that is valid for arbitrarily complex plasmas over a wide range of Coulomb couplings. The microscopic mixing rule in turn implies and validates the linear mixing rule (LMR) for the equation of state properties and also the LMR for the electrical and thermal conductivities of dense MCPs. To make our result as useful as possible, for the specific cases of electrical and thermal conductivities, we provide a simple analytic fit that is valid for arbitrarily complex MCPs over a wide range of Coulomb couplings. We compute the thermal conductivity for a representative compositional profile of the outer crust of an accreting neutron star in which hundreds of nuclear species can be present. We utilize our results to re-examine the so-called impurity parameter formalism as used to characterize impure plasmas.

Authors:
;  [1]
  1. Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
Publication Date:
OSTI Identifier:
21371947
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 703; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/703/1/994; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; ELECTRON-ION COLLISIONS; ELECTRONS; EQUATIONS OF STATE; MOLECULAR DYNAMICS METHOD; NEUTRON STARS; NEUTRONS; NUCLEAR REACTIONS; NUCLEOSYNTHESIS; PHOTOSPHERE; PLASMA; SCATTERING; SIMULATION; STRUCTURE FACTORS; THERMAL CONDUCTIVITY; X RADIATION; ATMOSPHERES; BARYONS; CALCULATION METHODS; COLLISIONS; DIMENSIONLESS NUMBERS; ELECTROMAGNETIC RADIATION; ELECTRON COLLISIONS; ELEMENTARY PARTICLES; EQUATIONS; FERMIONS; HADRONS; ION COLLISIONS; IONIZING RADIATIONS; LEPTONS; NUCLEONS; PHYSICAL PROPERTIES; RADIATIONS; SOLAR ATMOSPHERE; STARS; STELLAR ATMOSPHERES; SYNTHESIS; THERMODYNAMIC PROPERTIES

Citation Formats

Daligault, J, and Gupta, S. ELECTRON-ION SCATTERING IN DENSE MULTI-COMPONENT PLASMAS: APPLICATION TO THE OUTER CRUST OF AN ACCRETING NEUTRON STAR. United States: N. p., 2009. Web. doi:10.1088/0004-637X/703/1/994.
Daligault, J, & Gupta, S. ELECTRON-ION SCATTERING IN DENSE MULTI-COMPONENT PLASMAS: APPLICATION TO THE OUTER CRUST OF AN ACCRETING NEUTRON STAR. United States. https://doi.org/10.1088/0004-637X/703/1/994
Daligault, J, and Gupta, S. Sun . "ELECTRON-ION SCATTERING IN DENSE MULTI-COMPONENT PLASMAS: APPLICATION TO THE OUTER CRUST OF AN ACCRETING NEUTRON STAR". United States. https://doi.org/10.1088/0004-637X/703/1/994.
@article{osti_21371947,
title = {ELECTRON-ION SCATTERING IN DENSE MULTI-COMPONENT PLASMAS: APPLICATION TO THE OUTER CRUST OF AN ACCRETING NEUTRON STAR},
author = {Daligault, J and Gupta, S},
abstractNote = {The thermal conductivity of a dense multi-component plasma (MCP) is critical to the modeling of accreting neutron stars. To this end, we perform large-scale molecular dynamics simulations to calculate the static structure factor of the dense MCP in the neutron star crust from near the photosphere-ocean boundary to the vicinity of the neutron drip point. The structure factors are used to validate a microscopic linear mixing rule that is valid for arbitrarily complex plasmas over a wide range of Coulomb couplings. The microscopic mixing rule in turn implies and validates the linear mixing rule (LMR) for the equation of state properties and also the LMR for the electrical and thermal conductivities of dense MCPs. To make our result as useful as possible, for the specific cases of electrical and thermal conductivities, we provide a simple analytic fit that is valid for arbitrarily complex MCPs over a wide range of Coulomb couplings. We compute the thermal conductivity for a representative compositional profile of the outer crust of an accreting neutron star in which hundreds of nuclear species can be present. We utilize our results to re-examine the so-called impurity parameter formalism as used to characterize impure plasmas.},
doi = {10.1088/0004-637X/703/1/994},
url = {https://www.osti.gov/biblio/21371947}, journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 703,
place = {United States},
year = {2009},
month = {9}
}