Abstract
The primordial helium abundance Y p is important for cosmology and the ratio ΔY/ΔZ of the changes relative to primordial abundances constrains models of stellar evolution. While the most accurate estimates of Y p come from emission lines in extragalactic H II regions, they involve an extrapolation to zero metallicity which itself is closely tied up with the slope ΔY/ΔZ. Recently certain systematic effects have come to light in this exercise which make it useful to have an independent estimate of ΔY/ΔZ from fine structure in the main sequence of nearby stars. We derive such an estimate from Hipparcos data for stars with Z ≤ Z ⊙ and find values between 2 and 3, which are consistent with stellar models, but still have a large uncertainty.
Based on data from the ESA Hipparcos astrometry satellite
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References
Alonso, A., Arribas, S., and Martinez-Roger, C.: 1996, A&A Suppl. 117, 227.
Auer, L.H. and Mihalas, D.: 1972, Ap. J. Suppl. 24, 193.
Bell, R.A. and Gustafsson, B.: 1989, MNRAS 236, 263.
Brocklehurst, M.: 1972, MNRAS153, 471.
Carney, B.W., Latham, D.W., Laird, J.B., and Aguilar, L.: 1994, Astr. J. 107, 2240.
Cayrel, R.: 1968, Ap. J. 151, 997.
Cayrel de Strobel, G., Hauck, B., François, C., Thévenin, F., Friel, E., Mermilliod, M., and Borde, S.: 1992, A&A Suppl. 95, 273.
Chieffi, A., Straniero, O. and Salaris, M.: 1995, Ap. J. Lett. 445, L39.
Copi, C., Schramm, D.N., and Turner, M.S.: 1995, Science 267, 192.
Cox, J.P., and Giuli, R.T.: 1968, Principles of Stellar Structure, Gordon and Breach.
ESA: 1997, The Hipparcos and Tycho Catalogues, ESA SP-1200.
Faulkner, J.: 1967, Ap. J. 147, 617.
Fernandes, J., Lebreton, Y., and Baglin, A.: 1996, A&A 311, 127.
Hata, N., Scherrer, R.J., Steigman, G., Thomas, D., Walker, T.P., Bludman, S., and Langacker, P.: 1995, Phys. Rev. Lett. 75, 3977.
Hata, N., Scherrer, R.J., Steigman, G., Thomas, D., and Walker, T.P.: 1996, Ap. J. 458, 637.
Izotov, Y.I., Lipovetsky, V.A., Chaffee, F.H., Foltz, C.B., Guseva, N.G., and Kniazev, A.Y.: 1997, Ap. J. 476, 698.
Izotov, Y.I., Thum, T.X., and Lipovetsky, V.A.: 1997, Ap. J. Suppl. 108, 1.
King, J.R.: 1997, Astr. J., 113, 2302.
Melnick, J., Heydari-Malayeri, M., and Leisy, P.: 1992, A&A 253, 16.
Olive, K., Skillman, E D, and Steigman, G.: 1997, preprint astro-ph/96 11166.
Pagel, B.E.J. and Kazlauskas, A.: 1992, MNRAS 256, 49 P.
Pagel, B.E.J., Simonson, E.A., Terlevich, R.J., and Edmunds, M.G.: 1992, MNRAS255, 325. Pagel, B.E.J. and Tautvaisiene, G.: 1995, MNRAS 276, 505.
Perrin, M.-N., Hejlesen, P.M., Cayrel de Strobel, G., and Cayrel, R.: 1977, A&A 54, 779.
Pilyugin, L.: 1993, A&A 277, 42.
Salaris, M., Chieffi, A., and Straniero, O.: 1993, Ap. J. 414, 580.
Smits, D.P.: 1996, MNRAS 278, 683.
Songaila, A., Wampler, E.J., and Cowie, L.L.: 1997, Nature 385, 137.
Tytler, D., Fan, X.-M., and Buries, S.: 1996, Nature 381, 207.
van den Hoek, R.: 1997, Thesis, Amsterdam University.
Weinberg, D.H., Miralda-Escudé, J., Hernquist, L., and Katz, N.: 1997, astro-ph/97 01012.
Yang, J., Turner, M.S., Steigman, G., Schramm, D.N., and Olive, K.: 1994, Ap. J. 281, 493.
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Høg, E., Pagel, B.E.J., Portinari, L., Thejll, P.A., MacDonald, J., Girardi, L. (1998). Primordial Helium and ΔY/ΔZ from H II Regions and from Fine Structure in the Main Sequence Based on Hipparcos Parallaxes. In: Prantzos, N., Tosi, M., Von Steiger, R. (eds) Primordial Nuclei and Their Galactic Evolution. Space Sciences Series of ISSI, vol 4. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5116-0_11
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DOI: https://doi.org/10.1007/978-94-011-5116-0_11
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