Genesis of the heaviest elements in the milky way galaxy

Science

Volumn 299, Issue 5603, 2003, Pages 70-75

  Sneden, Christopher ^a   Cowan, John J ^a,b  

^a The University of Texas at Austin   (United States)

^b University of Oklahoma   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ASTROPHYSICS; CHEMICAL ELEMENTS; HEAVY METALS; NEUTRON SOURCES; THORIUM;

STARS;

GALAXIES;

BARIUM; ELEMENT; EUROPIUM; ISOTOPE; LANTHANIDE; METAL; PROTON; STRONTIUM; THORIUM;

COSMOLOGY;

AGE DETERMINATION; ASTRONOMY; ATOMIC PARTICLE; COSMOS; EVOLUTION; HISTORY; NEUTRON RADIATION; PRIORITY JOURNAL; RADIOACTIVITY; REVIEW;

EID: 0037414870     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.1077506     Document Type: Review

References (38)

1. N. Grevesse, A. J. Sauval, Space Sci. Rev. 85, 161 (1998).
2. The high temperatures that would be required (to overcome the electric Coulomb barriers) for fusion of nuclei beyond iron would also result in a large number of high-energy photons. These photons in turn result in photodisintegration of nuclei that suppress any possible charge-particle fusion reactions.
3. H fusion in stars occurs in the inner core (approximately the innermost 10% of the star by mass) and lasts for about 90% of the star's total life. After the exhaustion of H in the core, the star will then develop a thin (thousands of km) H fusion shell outside of the inert He core. Later, when the temperature rises to above 100 million K, the He core will fuse C and O. When the He is finally depleted in the core, a thin He fusion shell, outside of the now C/O core but interior to the H fusion shell, will ignite. These later fusion stages occur only during the last ∼10% of a star's life.
4. Supernovae (SNe) are observationally categorized by the presence (type II) or absence (type I) of hydrogen spectral lines. Further, type II SNe are normally thought to result from the collapse and explosion of single massive, short-lived stars. Type I SNe are thought to be phenomena of lower-mass, longer-lived binary star systems, with the eventual explosion and complete destruction of the white dwarf member of the binary.
5. A. G. W. Cameron, in Essays in Nuclear Astrophysics, C. A. Barnes, D. D. Clayton, D. N. Schramm, Eds. (Cambridge Univ. Press, Cambridge, 1982), pp. 23-43.
6. F. Käppeler, H. Beer, K. Wisshak, Rep. Prog. Phys. 52, 945 (1989).
7. D. L. Burris et al., Astrophys. J. 544, 302 (2000).
8. C. Arlandini et al., Astron. Astrophys. 525, 886 (1999).
9. Caution is recommended in interpreting the r-process fractions of isotopes with extreme dominance by the s-process: A small error (∼10%) in the s-process fraction in these cases leads to a large uncertainty (≥25%) in the remainder r-process fraction.
10. sun]. With this definition [Fe/H] is normally used as a surrogate for overall metallicity, and for example [Eu/Fe] tells the difference in stellar and solar Eu/Fe abundance ratios.
11. H. E. Bond, Astrophys. J. Suppl. Ser. 44, 517 (1980).
12. T. C. Beers, G. W. Preston, S. A. Shectman, Astron. J. 103, 1987 (1992).
13. A. McWilliam, G. W. Preston, C. Sneden, L. Searle, Astron. J. 109, 2757 (1995).
14. C. Sneden et al., Astrophys. J. 467, 819 (1996).
15. C. Sneden et al., Astrophys. J. 533, L139 (2000).
16. C. Sneden et al., in preparation.
17. J. W. Truran, J. J. Cowan, C. A. Pilachowski, C. Sneden, Publ. Astron. Soc. Pac. 114, 1293 (2002).
18. W. Aoki, J. E. Norris, S. G. Ryan, T. C. Beers, H. Ando, Astrophys. J. 576, 141 (2002).
19. -, Astrophys. J. 536, 97 (2000).
20. M. Busso, R. Gallino, G. J. Wasserburg, Annu. Rev. Astron. Astrophys. 37, 239 (1999).
21. J. J. Cowan et al., Astrophys. J. 572, 861 (2002).
22. V. Hill et al., Astron. Astrophys. 387, 560 (2002).
23. M. Spite, F. Spite, Astron. Astrophys. 67, 23 (1978).
24. J. Simmerer et al., in preparation.
25. H. R. Butcher, Nature 328, 127 (1987).
26. C. Sneden et al., Astrophys. J. 536, L85 (2000).
27. R. Cayrel et al., Nature 409, 691 (2001).
28. H. Schatz et al., Astrophys. J. 579, 626 (2002).
29. F. Pont, F. M. Mayor, C. Turon, D. A. Vandenberg, Astron. Astrophys. 329, 87 (1998).
30. A. G. Riess et al., Astron. J. 116, 1009 (1998).
31. S. Perlmutter et al., Astrophys. J. 517, 565 (1999).
32. J. E. Norris, S. G. Ryan, T. C. Beers, Astrophys. J. 561, 1034 (2001).
33. E. Depagne et al., Astron. Astrophys. 390, 187 (2002).
34. Y.-Z. Qian, G. J. Wasserburg, Astrophys. J. 559, 925 (2001).
35. E. M. Burbidge, G. R. Burbidge, W. A. Fowler, F. Hoyle, Rev. Med. Phys. 29, 547 (1957).
36. A. G. W. Cameron, Chalk River Report CRL-41 (1957).
37. P. Möller, J. R. Nix, K.-L. Kratz, At. Data Nucl. Data Tables 66, 131 (1997).
38. We thank our colleagues for helpful conversations and insightful comments, and P. Möller for providing us with a copy of Fig. 1. Supported by NSF grants AST-9987162 (C.S.) and AST-9986974 (J.J.C.), Space Telescope Science grant GO-08342, and the University of Texas at Austin Department of Astronomy John W. Cox Fund (J.J.C.).