Abstract
The discovery of technetium in red giant stars1 was a landmark in stellar nucleosynthesis theory. Because of the short half-lives of its isotopes, the presence of technetium has been regarded as irrefutable evidence for a recent episode of slow-neutron capture ('s-process') in asymptotic giant branch stars2–6. But the 100 or so stars with technetium lines in their spectra7, 8 (Tc stars) show the opposite correlation between metallicity and technetium production to that expected to result3, 4 ,9 from an s-process. Here we argue that the production of technetium in red giant stars is not necessarily related to an interior s-process mechanism, and that some observations of technetium in metal-rich (population I) red giants may be more readily explained by γ-ray-induced fission of heavy isotopes (atomic mass A≈ 240) initially present in the stellar envelope.
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References
Merrill, P. Astrophys. J. 116, 21–26 (1952).
Iben, I. Jr & Renzini, A. A. Rev. Astr. Astrophys. 21, 271–342 (1983).
Hollowell, D. E. thesis, Univ. of Illinois (1988).
Lattanzio, J. C. in Proc. Evolution of Peculiar Red Giant Stars, IAU Coll. 106, (Indiana Univ.) (1988).
Mathews, G. J., Takahashi, K., Ward, R. A. & Howard, W. M. Astrophys. J. 302, 410–414 (1986).
Malaney, R. A. Astrophys. J. 321, 832–845 (1987).
Little, S. J., Little-Marenin, I. R. & Hagen Bauer, W. Astr. J. 94, 981–995 (1987).
Smith, V. V. & Lambert, D. L. Astrophys. J. 333, 219–226 (1988).
Iben, I. Jr & Renzini, A. Astrophys. J. 259, L79–L83 (1983).
Harrison, T. G. Astrophys. Lett. 18, 7–12 (1976).
Harrison, T. G. Astrophys. Lett. 16, 87–95 (1975).
Dakowski, M. Earth planet. Sci. Lett. 6, 152 (1969).
Kuchowicz, B. Astrophys. Lett. 9, 85–89 (1971).
Kuroda, P. K. Nature 187, 36–38 (1960).
Alexander, E. C., Lewis, R. S., Reynolds, J. H. & Michel, M. D. Science 172, 837–840 (1971).
Selinov, I. P. in Proc. 2nd UN Int. Conf. on the Peaceful uses of Atomic Energy 30, 307–326 (Unit. Nations, Geneva, 1958).
Anders, E. & Ebihara, M. Geochim. cosmochim. Acta 46, 2362–2380 (1982).
Cowley, C. R. & Adelman, S. J. Astrophys. Lett. 16, 5–7 (1975).
Gorbachev, V. M., Zamyatnin, Y. S. & Lbov, A. A. Nuclear Reactions in Heavy Elements (Pergamon, Oxford, 1980).
Evans, R. D. The Atomic Nucleus (McGraw-Hill, New York, 1955).
Vandenbosch, R. & Huizenga, J. R. Nuclear Fission (Academic, New York, 1973).
Sweigart, A. V. & Gross, P. G. Astrophys. J. Suppl. 36, 405–437 (1978).
Boothroyd, A. I. & Sackmann, I.-J. Astrophys. J. 238, 671–679 (1988).
Smith, V. V. in Origin and Distribution of the Elements (ed. Mathews, G. J.) 535–541 (World Scientific, Singapore, 1988).
Smith, V. V. & Lambert, D. L. Astrophys. J. 311, 843–863 (1986).
Dominy, J. F. & Wallerstein, G. Astrophys. J. 310, 371–377 (1986).
Wallerstein, G. & Dominy, J. F. Astrophys. J. 330, 937–941 (1988).
Malaney, R. A., Mathews, G. J. & Dearborn, D. S. P. Astrophys. J. (submitted).
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Malaney, R. Production of technetium in red giants by γ- ray-induced fission. Nature 337, 718–720 (1989). https://doi.org/10.1038/337718a0
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DOI: https://doi.org/10.1038/337718a0
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