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Sodium abundance variations in main-sequence stars of the globular cluster 47 Tucanae

Nature volume 383, pages 604–606 (1996)Cite this article

Abstract

GALACTIC globular clusters were once thought to be chemically homogeneous, having formed quite rapidly from relatively small condensations of primordial gas29. In many clusters, significant star-to-star variations in light-element abundances have been observed1–4 in evolved giant stars. These variations have been attributed to the presence at the stellar surfaces of nucleosynthesis products generated deep within the stars. But other observations13 have suggested that some of this variability was established earlier in the stars' lifetimes, perhaps as a result of inhomogeneities in the gas cloud from which the cluster formed. Here we report the observation of variations in the sodium abundances of unevolved (main-sequence) stars in the cluster 47 Tucanae. Although these variations are similar to those observed in evolved cluster stars, they cannot be explained by mixing, in the framework of current models of stellar evolution. This indicates either that the gas out of which 47 Tuc formed was chemically inhomogeneous, or that some mechanism for altering the surface element abundances of stars operates while they are still on the main sequence.

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References

  1. Smith, G. H. Publ. Astron. Soc. Pacif. 99, 67–90 (1987).

    Article  ADS  CAS  Google Scholar 

  2. Suntzeff, N. B. in The Globular Cluster-Galaxy Connection (eds Smith, G. H. & Brodie, J. P.) 167–179 (ASP Conf. Ser. Vol. 48, Astronomical Society of the Pacific, San Francisco, 1993).

    Google Scholar 

  3. Briley, M. M., Bell, R. A., Hesser, J. E. & Smith, G. H. Can. J. Phys. 72, 772–781 (1994).

    Article  ADS  CAS  Google Scholar 

  4. Kraft, R. P. Publ. Astron. Soc. Pacif. 106, 553–565 (1994).

    Article  ADS  Google Scholar 

  5. Norris, J. & Freeman, K. C. Astrophys. J. 230, L179–L182 (1979).

    Article  ADS  CAS  Google Scholar 

  6. Cottrell, P. L. & Da Costa, G. S. Astrophys. J. 245, L79–L82 (1981).

    Article  ADS  CAS  Google Scholar 

  7. Gratton, R. L., Quarta, M. L. & Ortolani, S. Astron. Astrophys. 169, 208–218 (1986).

    ADS  CAS  Google Scholar 

  8. Brown, J. A. & Wallerstein, G. Astron. J. 104, 1818–1830 (1992).

    Article  ADS  CAS  Google Scholar 

  9. Langer, G. E. & Hoffman, R. Publ. Astron. Soc. Pacif. 107, 1177–1182 (1995).

    Article  ADS  Google Scholar 

  10. Cavallo, R. M., Sweigart, A. V. & Bell, R. A. Astrophys. J. 464, L79–L82 (1996).

    Article  ADS  CAS  Google Scholar 

  11. Sweigart, A. V. & Mengel, J. G. Astrophys. J. 229, 624–641 (1979).

    Article  ADS  CAS  Google Scholar 

  12. Charbonnel, C. Astron. Astrophys. 282, 811–828 (1994).

    ADS  CAS  Google Scholar 

  13. Briley, M. M., Hesser, J. E., Bell, R. A., Bolte, M. & Smith, G. H. Astron. J. 108, 2183–2192 (1994).

    Article  ADS  CAS  Google Scholar 

  14. Cayrell, R. in The Impact of Very High Signal to Noise Spectroscopy on Stellar Physics (eds Cayrell de Strobel, G. & Spite, M.) 345–353 (Kluwer, Dordrecht, Boston, 1988).

    Google Scholar 

  15. Sneden, C. Astrophys. J. 184, 839–849 (1973).

    Article  ADS  CAS  Google Scholar 

  16. Norris, J. & Freeman, K. C. Astrophys. J. 230, L179–L182 (1979).

    Article  ADS  CAS  Google Scholar 

  17. Bell, R. A., Dickens, R. J. & Gustafsson, B. Astrophys. J. 229, 604–623 (1979).

    Article  ADS  CAS  Google Scholar 

  18. Carbon, D. F. et al. Astrophys. J. Suppl. Ser. 49, 207–258 (1982).

    Article  ADS  CAS  Google Scholar 

  19. Trefzger, D. V., Langer, G. E., Carbon, D. F., Suntzeff, N. B. & Kraft, R. P. Astrophys. J. 266, 144–159 (1983).

    Article  ADS  CAS  Google Scholar 

  20. Sneden, C., Kraft, R. P., Prosser, C. F. & Langer, G. E. Astron. J. 104, 2121–2140 (1992).

    Article  ADS  CAS  Google Scholar 

  21. Kraft, R. P., Sneden, C., Langer, G. E. & Shetrone, M. D. Astron. J. 106, 1490–1507 (1993).

    Article  ADS  CAS  Google Scholar 

  22. Pilachowski, C. A., Sneden, C., Kraft, R. P. & Langer, G. E. Astron. J. 112, 545–564 (1996).

    Article  ADS  CAS  Google Scholar 

  23. Bell, R. A. & Dickens, R. J. Astrophys. J. 242, 657–672 (1980).

    Article  ADS  CAS  Google Scholar 

  24. Suntzeff, N. B. & Smith, V. V. Astrophys. J. 381, 160–172 (1991).

    Article  ADS  CAS  Google Scholar 

  25. Briley, M. M., Smith, V. V. & Lambert, D. L. Astrophys. J. 424, L119–L122 (1994).

    Article  ADS  CAS  Google Scholar 

  26. Hesser, J. E., Shott, P., Harris, W. E., Allwright, J. W. B. & VandenBerg, D. A. Publ. Astron. Soc. Pacif. 99, 739–808 (1987).

    Article  ADS  CAS  Google Scholar 

  27. Pilachowski, C. A., Sneden, C. & Kraft, R. P. Astron. J. 111, 1689–1704 (1996).

    Article  ADS  CAS  Google Scholar 

  28. Norris, J. E. & Da Costa, C. S. Astrophys. J. 447, 680–705 (1995).

    Article  ADS  CAS  Google Scholar 

  29. Murray, S. D. & Lin, D. N. Astrophys. J. 339, 933–942 (1989).

    Article  ADS  CAS  Google Scholar 

Download references

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Authors and Affiliations

  1. Department of Physics and Astronomy, University of Wisconsin Oshkosh, Oshkosh, Wisconsin, 54901, USA

    Michael M. Briley

  2. Department of Physics, University of Texas at El Paso, El Paso, Texas, 79968, USA

    Verne V. Smith

  3. McDonald Observatory, University of Texas, Austin, Texas, 78741, USA

    Verne V. Smith & David L. Lambert

  4. National Optical Astronomy Observatories, Cerro Tololo Inter-American Observatory, Casilla 603, La Serena, Chile

    Nicholas B. Suntzeff

  5. Department of Astronomy, University of Maryland, College Park, Maryland, 20742, USA

    Roger A. Bell

  6. Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council, 5071 Saanich Road, RR5, Victoria, British Columbia, V8X 4M6, Canada

    James E. Hesser

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  4. David L. Lambert
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  5. Roger A. Bell
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  6. James E. Hesser
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Briley, M., Smith, V., Suntzeff, N. et al. Sodium abundance variations in main-sequence stars of the globular cluster 47 Tucanae. Nature 383, 604–606 (1996). https://doi.org/10.1038/383604a0

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