J/A+A/625/A87 Ultra-massive white dwarfs evolution models (Camisassa+, 2019)
The evolution of ultra-massive white dwarfs.
Camisassa M.E., Althaus L.G., Corsico, A.H., De Geronimo F.C.,
Miller Bertolami M.M., Novarino M.L., Rohrmann R.D., Wachlin F.C.,
Garcia-Berro E.
<Astron. Astrophys. 625, A87 (2019)>
=2019A&A...625A..87C 2019A&A...625A..87C (SIMBAD/NED BibCode)
ADC_Keywords: Models, evolutionary ; Stars, white dwarf ; Stars, ages
Keywords: stars: evolution - stars: interiors - white dwarfs
Abstract:
Ultra-massive white dwarfs are powerful tools to study various
physical processes in the Asymptotic Giant Branch (AGB), type Ia
supernova explosions and the theory of crystallization through white
dwarf asteroseismology. Despite the interest in these white dwarfs,
there are few evolutionary studies in the literature devoted to them.
Here, we present new ultra-massive white dwarf evolutionary sequences
that constitute an improvement over previous ones. In these new
sequences, we take into account for the first time the process of
phase separation expected during the crystallization stage of these
white dwarfs, by relying on the most up-to-date phase diagram of dense
oxygen/neon mixtures. Realistic chemical profiles resulting from the
full computation of progenitor evolution during the semidegenerate
carbon burning along the super-AGB phase are also considered in our
sequences. Outer boundary conditions for our evolving models are
provided by detailed non-gray white dwarf model atmospheres for
hydrogen and helium composition. We assessed the impact of all these
improvements on the evolutionary properties of ultra-massive white
dwarfs, providing up-dated evolutionary sequences for these stars. We
conclude that crystallization is expected to affect the majority of
the massive white dwarfs observed with effective temperatures below
40000K. Moreover, the calculation of the phase separation process
induced by crystallization is necessary to accurately determine the
cooling age and the mass-radius relation of massive white dwarfs. We
also provide colors in the GAIA photometric bands for our H-rich white
dwarf evolutionary sequences on the basis of new models atmospheres.
Finally, these new white dwarf sequences provide a new theoretical
frame to perform asteroseismological studies on the recently detected
ultra-massive pulsating white dwarfs.
Description:
New ultra-massive ONe white dwarf evolutionary sequences that take
into account the process of phase separation expected during the
crystallization stage based on phase diagram of dense oxygen/neon
mixtures. Realistic chemical profiles resulting from the full
computation of progenitor evolution during the semi-degenerate carbon
burning along the super-AGB phase are also considered in our
sequences. Outer boundary conditions for our evolving models are
provided by detailed non-gray white dwarf model atmospheres for
hydrogen and helium composition. Magnitudes in GAIA filters are also
provided for our H rich white dwarf models.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
110hdef.dat 192 511 Evolutionary track of our 1.10Msun H-deficient model
110hrich.dat 192 748 Evolutionary track of our 1.10Msun H-rich model
110gaia.dat 164 609 Absolute magnitudes of the evolutionary track of
our 1.10Msun H-rich model in GAIA filters
116hdef.dat 192 738 Evolutionary track of our 1.16Msun H-deficient model
116hrich.dat 192 756 Evolutionary track of our 1.16Msun H-rich model
116gaia.dat 164 592 Absolute magnitudes of the evolutionary track of
our 1.16Msun H-rich model in GAIA filters
122hdef.dat 192 1111 Evolutionary track of our 1.22Msun H-deficient model
122hrich.dat 192 717 Evolutionary track of our 1.22Msun H-rich model
122gaia.dat 164 562 Absolute magnitudes of the evolutionary track of
our 1.22Msun H-rich model in GAIA filters
129hdef.dat 192 698 Evolutionary track of our 1.29Msun H-deficient model
129hrich.dat 192 831 Evolutionary track of our 1.29Msun H-rich model
129gaia.dat 164 650 Absolute magnitudes of the evolutionary track of
our 1.29Msun H-rich model in GAIA filters
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Byte-by-byte Description of file (#): *hdef.dat *hrich.dat
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Bytes Format Units Label Explanations
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1- 9 F9.6 [Lsun] logL Logarithm of the surface luminosity
in solar units
11- 19 F9.6 K logTeff Logarithm of the effective temperature
21- 29 F9.6 10+6K logTc Logarithm of the central temperature
(million degree)
31- 39 F9.6 [g/cm3] logRoc Logarithm of the central density (CGS units)
41- 49 F9.6 --- Hc Central hydrogen abundance
51- 59 F9.6 --- Hec Central helium abundance
61- 66 F6.3 % Cons Percentage of mass of the
outer convective zone
68- 73 F6.3 % Conc Percentage of mass of the
inner convective zone
75- 94 F20.15 [Myr] log(edad) Logarithm of the total age in million years
counted from an arbitrary starting point (1)
96-103 F8.5 Msun M* Stellar mass (in solar units)
105-113 F9.5 Msun/yr dM/dt Mass loss
115-125 F11.7 [Lsun] log(Lnu) Logarithm of luminosity (in solar units) due
to neutrino losses
127-137 F11.7 [Msun] logMHtot ? Logarithm of the hydrogen content
in solar mass
138 A1 --- n_logMHtot [I] I for -Infinity
140-150 F11.7 [cm/s2] logg Logarithm of surface gravity (CGS units)
152-162 F11.7 Rsun Rad Stellar radius in solar units
164-177 E14.7 10-7W LH Energy released as latent heat during
crystallization (CGS units)
179-192 E14.7 10-7W SepFase Energy released by phase separation during
crystallization (CGS units)
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Note (1): to obtain the white dwarf cooling time, the first value of this column
must be considered as the starting point.
The cooling time is defined as zero at the moment when the star reaches the
maximum effective temperature. In order to accurately obtain the white dwarf
cooling time, the zero point in the stellar age has to be obtained when the
effective temperature reaches the maximum value.
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Byte-by-byte Description of file: *gaia.dat
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Bytes Format Units Label Explanations
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3- 14 E12.7 K Teff Logarithm of the effective temperature
16- 29 E14.7 [Lsun] logL Logarithm of the surface luminosity
in solar units
31- 44 E14.7 Gyr Age Cooling time in Gyr (109yr) (starting point
at the beginning of the cooling sequence)
46- 59 E14.7 [cm/s2] logg Logarithm of surface gravity (CGS units)
61- 74 E14.7 Rsun Rad Stellar radius in solar units
76- 89 E14.7 mag GMAG Absolute Magnitude in the Gaia band G
91-104 E14.7 mag BPMAG Absolute Magnitude in the Gaia band BP
106-119 E14.7 mag RPMAG Absolute Magnitude in the Gaia band G
121-134 E14.7 mag BP-G Color index BP-G
136-149 E14.7 mag G-RP Color index G-RP
151-164 E14.7 mag BP-RP Color index BP-RP
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Acknowledgements:
Maria E. Camisassa, camisassam(at)googlemail.com
(End) Maria Camisassa [La Plata, Argentina], Patricia Vannier [CDS] 20-Mar-2019