J/A+A/546/A119 Outer boundary conditions for evolving cool WD (Rohrmann+, 2012)
Outer boundary conditions for evolving cool white dwarfs.
Rohrmann R.D., Althaus L.G., Garcia-Berro E., Corsico A.H.,
Miller-Bertolami M.M.
<Astron. Astrophys. 546, A119 (2012)>
=2012A&A...546A.119R 2012A&A...546A.119R
ADC_Keywords: Stars, white dwarf ; Models, evolutionary
Keywords: stars: evolution - stars: interiors - stars: white dwarfs
Abstract:
White dwarf evolution is essentially a gravothermal cooling process,
which, for cool white dwarfs, depends on the treatment of the outer
boundary conditions. We provide detailed outer boundary conditions
that are appropriate to computing the evolution of cool white dwarfs
by employing detailed nongray model atmospheres for pure hydrogen
composition. We also explore the impact on the white dwarf cooling
times of different assumptions for energy transfer in the atmosphere
of cool white dwarfs.
Description:
Outer boundary conditions (temperature, pressure, outer stellar mass
and geometrical depth) at a Rosseland mean optical depth 25.1189, for
effective temperatures between 2000K and 40000K, and 5.5<logg<9.0.
These calculations, based on detailed stellar atmosphere models, are
appropriated for computing the evolution of cool white dwarfs with
hydrogen envelopes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table.dat 66 15621 Temperature (T), pressure (P), geometrical depth
(X), and stellar mass in outer layers, Mr/M
(relative to the total stellar mass), for a
Rosseland mean optical depth τ=25.11886
(logτ=1.4)
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See also:
J/ApJ/631/1100 : Atmospheric parameters of DA white dwarfs (Gianninas+, 2005)
J/MNRAS/399/699 : Parameters of atmospheres of white dwarfs (Mortlock+, 2009)
Byte-by-byte Description of file: table.dat
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Bytes Format Units Label Explanations
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4- 10 F7.1 K Teff [2000/40000] Effective temperature
14- 16 F3.1 [cm/s2] log(g) [5.5/9.5] Surface gravity acceleration (1)
17- 18 A2 --- --- [00]
22- 30 F9.6 [10+6K] ln(T6) Temperature [106K] (1)
33- 42 F10.6 [10+14Pa] ln(P15) Pressure [1015dyn/cm2] (1)
45- 54 F10.6 [---] ln(Mr/M) Outer mass relative to the total stellar
mass (1)
57- 66 F10.6 [10+8m] ln(X) Geometrical depth [1010cm] (1)
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Note (1): ln for natural logarithm, log for logarithm to base 10.
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Acknowledgements:
R. Rohrmann, rohr(at)icate-conicet.gob.ar
(End) R. Rohrmann [ICATE, UNSJ-CONICET], Patricia Vannier [CDS] 20-Sep-2012