Abstract
The process of element segregation in stars (also called "microscopic diffusion") has to be introduced in all computations of stellar structure to obtain consistent models. Although recognized by the pioneers of stellar physics, this process has long been forgotten, except for white dwarfs and for the so-called "chemically peculiar stars". More recently helioseismology has given evidence that this process occurs in the Sun, and leads to helium and heavier element depletion by about 20 percent. Some macroscopic motions (mild mixing) must also occur below the convection zone in order to account for the lithium depletion. These motions do not prevent the segregation : they only slightly smooth the abundance gradients. These results are presented here and the connexion with the 3He abundance is discussed. The importance of these processes for Pop II stars is also developped.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Alexander, D.R., Fergusson, J.W.: 94, ApJ 437, 879.
Bahcall, J.N., Pinsonneault, M.H.: 1992, Reviews of Modern Physics 64, 885.
Balachandran, S.: 1997, preprint
Basu, S.: 1997, preprint.
Bonifacio, P., Molaro, P.: 1997, MNRAS 285, 847.
Charbonnel, C., Vauclair, S., Zahn, J.P.: 1992, A&A 255, 191 (CVZ).
Charbonnel, C., Däppen, W., Bernasconi, P.A., Maeder, A., Meynet, G., Schaerer, D., Mowlavi, N.: 1997, A&A, submitted.
Cox, A.N., Guzik, J.A., Kidman, R.B.: 1989, ApJ 342, 1187.
Dziembowski, W.Q., Goode, P.R., Pamyatnikh, A.A., Sienkiewicz, R.: 1994, ApJ 432, 417.
Gautier and Morel: 1997 A&A 323, L9.
Geiss, J., Buhler, F., Cerutti, H., Eberhardt, P., Filleux, Ch.: 1972, Apollo Preliminary Science Report, NASA SP-315, section 14.
Geiss, J.: 1993, Origin and Evolution of the Elements, ed. Prantzos, Vangioni-Flam, and Cassé (Cambridge Univ. Press), 90.
Gloecker, G., Geiss, J.: 1997, preprint.
Grevesse, N.: 1991, A&A 242, 488.
Hobbs, L., Thorburn, J.A.: 1994, ApJ 428, L25.
Iglesias, C.A., Rogers, F.J.: 1996, ApJ 464, 943.
Michaud, G.: 1970, ApJ 160, 641.
Mihalas, D., Hummer, D.G., Däppen, W.: 1988, ApJ 331, 815.
Morel, P., Schatzman, E.: 1996, A&A 310, 982.
Paquette, C., Pelletier, C., Fontaine, G., Michaud, G.: 1986, ApJS 61, 177.
Proffitt, C.R.: 1994, ApJ 425, 849.
Richard, O., Vauclair, S., Charbonnel, C., Dziembowski, W.A.: 1996, A&A 312, 1000.
Richard, O., Vauclair, S.: 1997, A&A 322, 671.
Ryan, S.G., Beers, T.C., Deliyannis, C.P., Thorburn, J.: 1996, ApJ 458, 543.
Schatzman, E.: 1945, Ann. d'Astr. 8, 143.
Schramm, D.: 1998, Space Sci. Rev., this volume.
Smith, V.V., Lambert, D.L., Nissen, P.E.: 1992, ApJ 408, 262.
Spite, M., Spite, F.: 1982, A&A 115, 357.
Spite, M., François, P., Nissen, P.E., Spite, F.: 1996, A&A 307, 172.
Thorburn, J.A.: 1994, ApJ 421, 318.
Thoul, A.A., Bahcall, J.N., Loeb, A.: 1994, ApJ 421, 828.
Vauclair, S., Vauclair, G.: 1982, ARA&A 20, 37.
Vauclair, S., Charbonnel, C.: 1995, A&A 295, 715.
Vauclair, S., Charbonnel, C.: 1997, preprint.
Vauclair, S., Richard, O.: 1997a, Proceedings of the Los Alamos meeting A half century of stellar pulsation interpretations: a tribute to Arthur N. Cox″, June 16–20, 1997.
Vauclair, S., Richard, O.: 1997b, preprint.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Vauclair, S. Evidence of Element Diffusion Inside the Sun and the Stars and its Consequences on the Lithium Primordial Abundance. Space Science Reviews 84, 265–271 (1998). https://doi.org/10.1023/A:1005043923432
Issue Date:
DOI: https://doi.org/10.1023/A:1005043923432