J/A+A/547/A96 Low-mass He-core white dwarfs seismic properties (Corsico+, 2012)
The seismic properties of low-mass He-core white dwarf stars.
Corsico A.H., Romero A.D., Althaus L.G., Hermes J.J.
<Astron. Astrophys. 547, A96 (2012)>
=2012A&A...547A..96C 2012A&A...547A..96C
ADC_Keywords: Models ; Stars, white dwarf ; Abundances
Keywords: asteroseismology - stars:oscillations - white dwarfs -
stars: evolution - stars: interiors
Description:
We present detailed tabulations of stellar models and pulsational
properties for low-mass He-core white dwarf stars, for different
stellar masses and effective temperatures. Pulsation periods were
computed for g- and p-modes with harmonic degree l=1. The stellar mass
ranges from 0.17M_☉ to 0.45M_☉, while the effective
temperature ranges from 13000 to 8000K. The pulsation periods are
listed in files named avam.mmmg.tgz and avam.mmmp.tgz, for g- and
p-modes, respectively, were m.mmm denotes the stellar mass in solar
mass units. These files contain a sequence of tables
(avannnm.mmmg.out and avannnm.mmmp.out) corresponding to models
with decreasing effective temperature, where nnn correspond to the
number of file, starting with nnn=001. In each avannnm.mmmg.out and
avannnm.mmmp.out files, the following quantities are listed:
harmonic degree (l), radial order (k), Period, period spacing (DP),
kinetic energy (log(Ek)) and first order rotation splitting
coefficient (C_kl). The stellar parameters characterizing each model
are listed at the top of the table as a header: stellar mass in solar
units (M*/M☉), luminosity in solar units (L*/L☉),
effective temperature in Kelvin (Teff[K]), hydrogen mass in units of
the stellar mass (log(MH/M*)), age in millions of years (Time
[106yr]), and asymptotic period spacing in seconds (DPa [s], for
g-modes only). The chemical profiles and critical frequencies are
listed in the files par_m.mmm.tgz, which contain a sequence of tables
corresponding to models with decreasing effective temperature
(parnnn_m.mmm.out). Stellar parameters of each model are listed as a
header: stellar mass in solar units (M*/M☉), effective
temperature in Kelvin (Teff[K]), luminosity in solar units
(L*/L☉) and hydrogen mass in units of stellar mass
(log(MH/M*)). Below the header, the following quantities are listed:
normalized radial coordinate (r/R_*), the outer mass fraction
coordinate (-log q, with q=1-Mr/M*), the squared Brunt-Vaisala
(N2) and Lamb (L2) frequencies, the Ledoux term (B Ledoux), and
the abundances by mass of hydrogen (H1), helium (He4), carbon (C12)
and oxygen (O16).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ava_g.dat 123 44871 *Pulsation periods for g-modes with harmonic degree l=1
ava_p.dat 127 30338 *Pulsation periods for p-modes with harmonic degree l=1
par.dat 143 166873 Chemical profiles and critical frequencies
files/* . 24 Original files (avam.mmm?.tgz and par_m.mmm.tgz)
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Note on ava_g.dat: list g-modes with periods shorter than 6000s.
Note on ava_p.dat: list p-modes with with radial order K<50.
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See also:
J/MNRAS/399/699 : Parameters of atmospheres of white dwarfs (Mortlock+, 2009)
J/A+A/465/249 : Age and colors of massive white dwarf stars (Althaus+, 2007)
Byte-by-byte Description of file: ava_[gp].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Mod [1/95] Model number (1)
5- 11 F7.5 Msun M* [0.16985/0.45219] Model stellar mass (G1)
13- 26 E14.9 Lsun L* [0.0007347/0.12594] Model stellar luminosity
28- 37 F10.4 K Teff [7006.28/14223.5] Model effective temperature
39- 44 F6.3 [-] logMH/M* [-3.44/-1.87] Model hydrogen mass in
stellar mass units
46- 54 F9.3 Myr Age [11495.5/16446.7] Model age
56- 65 F10.6 s DPa ? Model asymptotic period spacing
(for g-mode only)
67 I1 --- l [1] Harmonic degree
69- 71 I3 --- k [1/100] Radial order
73- 85 F13.8 s Per [0.501/5999.96] Pulsation period
87-102 E16.8 s DP [-37.740/159.925] Period spacing
104-112 F9.6 [10-7J] log(Ek) [38.8704/48.9739] Kinetic energy
114-127 E14.8 --- Ckl [-0.01261/0.88858] First order rotation
splitting coefficient
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Note (1): In general, there exists no correspondence between the pairs of
files ava0010.170g.out and ava0010.170p.out (for instance), here
same Num and M* in ava_g.dat and ava_p.dat, in the sense that, in
spite of the fact that both files share the same numbering (nnn=001),
they correspond to stellar models with different effective
temperatures. This holds in general for all the files
avannnm.mmmg.out and avannnm.mmmp.out with the same nnn and
stellar mass (m.mmm).
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Byte-by-byte Description of file: par.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Mod [1/18] Model number
5- 11 F7.5 Msun M* [0.16985/0.45219] Model stellar mass (G1)
13- 22 F10.4 K Teff [7015.53/13983.6] Model effective temperature
24- 37 E14.8 Lsun L* [0.0007347/0.12594] Model stellar luminosity
39- 44 F6.3 [-] logMH/M* [-3.431/-1.886] Model hydrogen mass in
stellar mass units
46- 55 E10.5 --- r/R* [0/1] Normalized radial coordinate
57- 66 E10.5 [-] mlogq [0/15.85] Outer mass fraction coordinate,
-logq (with q=1-Mr/M*)
68- 77 E10.5 --- N+2 [0/37.16] Squared Brunt-Vaisala frequency
79- 88 E10.5 --- L+2 [0/104.7] Squared Lamb frequency
90- 99 E10.5 --- BLedoux [0/1.58] Ledoux term
101-110 E10.5 --- H1 [-1.81e-38/0.9967] Hydrogen abundance by mass
112-121 E10.5 --- He4 [0/0.9905] Helium abundance by mass
123-132 E10.5 --- C12 [0/0.0007] Carbon abundance by mass
134-143 E10.5 --- O16 [0/0.0088] Oxygen abundance by mass
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Globle notes:
Note (G1): Model stellar mass studies:
0.16985, 0.19802, 0.22047, 0.25053, 0.30316, 0.35807, 0.40002 and 0.45219
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Acknowledgements:
Alejandro Corsico, acorsico(at)fcaglp.unlp.edu.ar
Alejandra Romero, aromero(at)fcaglp.unlp.edu.ar
(End) Patricia Vannier CDS 11-Oct-2012