Progress towards a unified equation of state

  • Werner Däppen
Part II Physical Processes in Modelling the Sun
Part of the Lecture Notes in Physics book series (LNP, volume 367)


A recent comparison of thermodynamical quantities, computed in the chemical and physical picture, has revealed a remarkable agreement in the hydrogen and helium ionization zones (on an isochore of log p = -5.5, with p in g cm−3). This agreement is due to an unexpectedly dominating (classical) Coulomb pressure term. The analogous comparison at a somewhat higher density (log p = −3.5) shows still striking similarities, despite the different treatment of bound states in the two formalisms. The results suggest use of a relatively simple parametrized equation of state for solar purposes.


Partition Function Cluster Coefficient Thermodynamical Quantity Physical Picture Cluster Expansion 
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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • Werner Däppen
    • 1
    • 2
  1. 1.Space Science Department of ESAESTECNoordwijkThe Netherlands
  2. 2.Institute for Theoretical PhysicsUniversity of CaliforniaSanta BarbaraUSA

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