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White Dwarf Crystallization

Published online by Cambridge University Press:  12 April 2016

Enrique Garcia-Berro
Affiliation:
Departamento de Física Aplicada. , Universidad Politécnica de Cataluña, Jordi Girona Salgado 31, 08034 Barcelona, Spain
Margarida Hernanz
Affiliation:
Centre d’Estudis Avançats de Blanes, C.S.I.C., Camí de Santa Bárbara, 17300 Blanes, Spain

Abstract

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The inclusion of a detailed treatment of solidification processes in the cooling theory of carbon–oxygen white dwarfs is of crucial importance for the determination of their luminosity function. Carbon–oxygen separation at crystallization yields delays larger than 2 Gyr to cool down to luminosities corresponding to the observed cut–off. This leads to estimates of the age of the galactic disk 1.5 to 2 Gyr older than the ones obtained in previous studies (about 9 Gyr). Furthermore, the presence of minor chemical species, in particular 22Ne, alters significantly the crystallization process, and produces extra delays of 2 to 3 gigayears. However, the detailed computation of the theoretical white dwarf luminosity function, taking into account a reasonable model of galactic chemical evolution, and including the effect of these species, shows that the location of the cut–off, and then the estimated age of the disk, is not modified significantly.

Type
Reviews
Copyright
Copyright © Cambridge University Press 1994

References

Abia, C., Canal, R., Isern, J., Ap. J, 366, 198, (1991)CrossRefGoogle Scholar
Abrikosov, A.A., Zh. Eksp. i Teor. Fiz., 39, 1798 (Soviet Phys. JETP 12, 1254), (1960)Google Scholar
Clayton, D.D., Ap. J, 285, 411, (1984)CrossRefGoogle Scholar
Barrat, J.L., Hansen, J.P., Mochkovitch, R., 1988, As. Astr., 199, 15, (1988)Google Scholar
Bravo, E., Isern, J., Canal, R., As. Ast., 270, 288, (1993)Google Scholar
Chabrier, G., Segretain, L., Hernanz, M., Isern, J., Mochkovitch, R. in White Dwarfs: Advances in Observation and Theory (Dordrecht: Kluwer Academic publishers) in press, (1993)Google Scholar
D’Antona, F., Mazzitelli, I., Ap. J, 347, 934, (1989)CrossRefGoogle Scholar
Fleming, T.A., Liebert, J., Green, R.F., Ap. J 308, 176, (1986)CrossRefGoogle Scholar
García–Berro, E., Hernanz, M., Isern, J., Mochkovitch, R., Nature 333, 642, (1988a)CrossRefGoogle Scholar
García–Berro, , Hernanz, M., Mochkovitch, R., Isern, J., As. Astr., 193, 141, (1988b)Google Scholar
Iben, I., Laughlin, G., Ap. J, 341, 312, (1989)CrossRefGoogle Scholar
Iben, I., Tutukov, A.V., Ap. J, 282, 615, (1984)CrossRefGoogle Scholar
Iyetomi, H., Ogata, S., Ichimaru, S., Ap. J 297, 17, (1988)Google Scholar
Isern, J., García–Berro, E., Hernanz, M., Mochkovitch, R., White Dwarfs (Berlin: Springer Verlag), 278, (1989a)Google Scholar
Isern, J., García–Berro, E., Hernanz, M., Mochkovitch, R., Evolutionary Phenomenae in Galaxies (Cambridge: Cambridge University Press), 224, (1989b)Google Scholar
sern, J., Mochkovitch, R., García–Berro, E., Hernanz, M., A. Astr., 241, 29, (1991)Google Scholar
Kirshnitz, D.A., Zh. Eksp. i Teor. Fiz., 38, 503 (Soviet Phys. JETP 11, 365), (1960)Google Scholar
Lamb, D.Q., Van Horn, U.M., Ap. J., 200, 306, (1975)CrossRefGoogle Scholar
Liebert, J., Dahn, C.C., Monet, D.G., Ap. J 332, 891, (1988)CrossRefGoogle Scholar
Mazzitelli, I., D’Antona, F., Ap. J, 308, 706, (1986)CrossRefGoogle Scholar
Mestel, L., MNRAS 112, 583, (1952)CrossRefGoogle Scholar
Mochkovitch, R., As. Astr. 122, 212, (1983)Google Scholar
Monet, D.G., Dahn, C.C., Vrba, F.J., Harris, H.C., Pier, J.R., Luginbuhl, C.B., Abies, H.D., AJ, 103, 638, (1992)CrossRefGoogle Scholar
Noh, H.R., Scalo, J., Ap. J, 352, 605, (1990)CrossRefGoogle Scholar
Salpeter, E.E., 1961, Ap. J 134, 669, (1961)Google Scholar
Segretain, L., Chabrier, G., As. Astr., 271, 13, (1993)Google Scholar
Stevenson, D.J., J.Phys. Suppl. 41, C253, (1980)Google Scholar
Van Horn, H.M., Phys. Lett. A, 28, 706, (1969)CrossRefGoogle Scholar
Winget, D.E., Hansen, C.J., Liebert, J., Van Horn, H.M., Fontaine, G., Nather, R.E., Kepler, S.O., Lamb, D.Q., Ap. J, 315, 77, (1987)CrossRefGoogle Scholar
Wood, M.A., Ap. J 386, 536, (1992)CrossRefGoogle Scholar
Wood, M.A., Winget, D.E., in IAU Colloq. 114, White Dwarfs (Berlin: Springer–Verlag), 282, (1989)Google Scholar
Xu, Z.M., VanHorn, U.M., Ap. J, 387, 662, (1992)CrossRefGoogle Scholar
Yuan, J.W., As. Astr., 224, 108, (1989)Google Scholar
Yuan, J.W., As. Astr., 261, 105, (1992)Google Scholar