Seismic Diagnostics of Mixing Beyond the Convective Core in Intermediate Mass Main-Sequence Stars

• Autorzy: Popielski B. L. , Dziembowski W. A.
• Języki publikacji: EN

Abstrakty

EN

We study prospects for seismic sounding the layer of a partial mixing above the convective core in main-sequence stars with masses in the 1.2-1.9 M_solar range. There is an initial tendency to increase of the convective core mass in such stars and this leads to ambiguities in modeling. Solar-like oscillations are expected to be excited in such objects. Frequencies of such oscillations provide diagnostics, which are sensitive to the structure of the innermost part of the star and they are known as the small separations. We construct evolutionary models of stars in this mass range assuming various scenarios for element mixing, which includes formation of element abundance jumps, as well as semiconvective and overshooting layers. We find that the three point small separations employing frequencies of radial and dipole modes provide the best probe of the element distribution above the convective core. With expected accuracy of frequency measurement from the space experiments, a discrimination between various scenarios should be possible.

Słowa kluczowe

EN

stars: oscillations; stars: evolution; convection

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2005
• Tom: Vol. 55, No. 2
• Strony: 177--193
• Opis fizyczny: Bibliogr. 24 poz., tab., wykr.

Twórcy

autor

Popielski B. L.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warsaw, Poland

autor

Dziembowski W. A.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warsaw, Poland
• Nicolaus Copernicus Astronomical Center, ul. Bartycka 18, 00-716 Warsaw, Poland

Bibliografia

• Alexander, D.R., and Ferguson, J.W. 1994, Astrophys. J., 437, 879.
• Baglin, A., Auvergne, M., Barge, P., Buey, J.T., Catala, C., Michel, E., Weiss, W., and the COROT Team 2002, Proc. of 1st Eddington workshop, "Stellar Structure and Habitable Planet Finding", 17, http://corot.asrsp-mrs.fr/.
• Biello, J.A. 2001, astro-ph/0102338.
• Christensen-Dalsgaard, J., and Frandsen, S. 1988, Advances in Helio- and Asteroseismology, IAU Symp., D. Reidel Publ. Co., Dordrecht, 123, 295.
• Crowe, R.A., and Mitalas, R. 1982, Astron. Astrophys., 108, 55.
• Dziembowski, W.A. 1977, Acta Astron., 27, 95.
• Grevesse, N., and Noels, A. 1993, Phys. Scr., T47, 133.
• Houdek, G., Balmforth, N.J., Christensen-Dalsgaard, J., and Gough, D.O. 1999, Astron. Astrophys., 351, 582.
• Iglesias, C.A., and Rogers, F.J. 1996, Astrophys. J., 464, 943.
• Kato, S. 1966, Publ. Astron. Soc. Japan, 18, 374.
• Ledoux, P. 1947, Astrophys. J., 105, 305.
• Martić, M., Lebrun, J.-C., Appourchaux, T., and Korzennik, S.G. 2004, Astron. Astrophys., 418, 295.
• Rogers, F.J. 2001, Contributions to Plasma Physics, 41, 179.
• Roxburgh, I.W. 1993, PRISMA, Report of Phase a Study, Eds. T. Appourchaux, et al. ESA SCI(93), p. 31.
• Roxburgh, I.W., and Favata, F. 2003, Astrophysics and Space Science, 284, 17.
• Roxburgh, I.W., and Vorontsov, S.V. 1994, MNRAS, 267, 297.
• Schwarzschild, M. 1906, Gott. Nach., 1, 41.
• Schwarzschild, M., and Härm, R 1958, Astrophys. J., 128, 348.
• Shaller, G., Shaerer, D., Meynet, G., and Maeder, A. 1992, Astron. Astrophys. Suppl. Ser., 96, 269.
• Spruit, H.C. 1992, Astron. Astrophys., 253, 131.
• Stevenson, D.J. 1979, MNRAS, 187, 129.
• Tassoul, M. 1990, Astrophys. J., 358, 313.
• VandenBerg, D.A. 1985, Astron. Astrophys. Suppl. Ser., 58, 711.
• Walker, G., et al. 2003, PASP, 115, 1023.