J/A+A/672/L1 Non-ideal Mixing Effects in the H-He EOS (Howard+, 2023)
Accounting for non ideal mixing effects in the hydrogen-helium
equation of state.
Howard S., Guillot T.
<Astron. Astrophys. 672, L1 (2023)>
=2023A&A...672L...1H 2023A&A...672L...1H (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Planets
Keywords: planets and satellites: interiors -
planets and satellites: gaseous planets -
planets and satellites: composition -
planets and satellites: individual: Jupiter - equation of state
Abstract:
The equation of state for hydrogen and helium is fundamental to study
stars and giant planets. It has been shown that, because of
interactions at atomic and molecular levels, the behaviour of a
mixture of hydrogen and helium cannot be accurately represented by
considering these elements separately.
Using on the one hand ab initio simulations which involve a system of
interacting hydrogen and helium particles and pure equations of state
for hydrogen and helium on the other, we derive the contributions in
density and entropy of the interactions between hydrogen and helium
particles.
Description:
We provide a table which contains the volume and entropy of mixing as
a function of pressure and temperature. This table is to be combined
with pure hydrogen and pure helium equations of state to obtain an
equation of state which self-consistently includes mixing effects for
any hydrogen and helium mixing ratio and may be used to model the
interior structure and evolution of giant planets to brown dwarfs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 75 53361 Table of the mixing terms
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 19 F19.16 [cm-2] logP Pressure in Log (in dyn/cm2 unit)
21- 24 F4.2 [K] logT Temperature in Log
26- 49 E24.17 cm+3/g Vmix Volume of mixing
51- 75 F25.10 10-7J/g/K Smix Entropy of mixing (in erg/g/K unit)
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Acknowledgements:
Saburo Howard, saburo.howard(at)oca.eu
(End) Patricia Vannier [CDS] 06-Feb-2023