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Astrophysics and Space Science

, Volume 307, Issue 1–3, pp 273–277 | Cite as

He Conductivity in Cool White Dwarf Atmospheres

  • S. Mazevet
  • M. Challacombe
  • P. M. Kowalski
  • D. Saumon
Original Article

Abstract

We investigate the conductivity of warm dense helium under conditions found in the atmospheres of cool white dwarfs using ab initio simulations. The calculations performed consist of quantum molecular dynamics simulations where the electronic wavefunction at each time step is obtained using density functional theory, while the ion trajectories are calculated using the resulting quantum mechanical forces. We use both conventional DFT (PW91) and hybrid (PBE0) functionals to calculate the conductivities that provide an estimate of the ionization fraction. While the calculations are in good agreement with the measurements for the equation of state, a significant discrepancy exists with the recently measured conductivity.

Keywords

Atomic processes Dense matter Equation of state Plasmas Radiation mechanisms:general 

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Copyright information

© Springer Science+Business Media B.V. 2006

Authors and Affiliations

  • S. Mazevet
    • 1
  • M. Challacombe
    • 1
  • P. M. Kowalski
    • 2
  • D. Saumon
    • 1
    • 2
  1. 1.Theoretical DivisionLos Alamos National LaboratoryLos AlamosUSA
  2. 2.Applied Physics DivisionLos Alamos National LaboratoryLos AlamosUSA

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