Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-25T02:31:14.140Z Has data issue: false hasContentIssue false
  • English
  • Français

Observational signatures for depletion in the Spite plateau: solving the cosmological Li discrepancy?

Published online by Cambridge University Press:  23 April 2010

Jorge Meléndez ,
Luca Casagrande ,
Iván Ramírez ,
Martin Asplund  and
William J. Schuster
Jorge Meléndez
Affiliation:
Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal email: [email protected]
Luca Casagrande
Affiliation:
Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, Postfach 1317, D-85741 Garching, Germany
Iván Ramírez
Affiliation:
Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, Postfach 1317, D-85741 Garching, Germany
Martin Asplund
Affiliation:
Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, Postfach 1317, D-85741 Garching, Germany
William J. Schuster
Affiliation:
Observatorio Astronómico Nacional, UNAM, Apartado Postal 877, Ensenada, BC, CP 22800, Mexico
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We present Li abundances for 73 stars in the metallicity range −3.5 < [Fe/H] < −1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality equivalent widths (σEW ~ 3%). At all metallicities we uncover a fine-structure in the Li abundances of Spite plateau stars, which we trace to Li depletion that depends on both metallicity and mass. Models including atomic diffusion and turbulent mixing seem to reproduce the observed Li depletion assuming a primordial Li abundance ALi = 2.64 dex (MARCS models) or 2.72 (Kurucz overshooting models), in good agreement with current predictions (ALi = 2.72) from standard BBN. We are currently expanding our sample to have a better coverage of different evolutionary stages at the high and low metallicity ends, in order to verify our findings.

Keywords

nucleosynthesis – cosmology: observations – stars: abundancesPopulation II
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 5 , Symposium S268: Light Elements in the Universe , November 2009 , pp. 211 - 214
Copyright
Copyright © International Astronomical Union 2010

References

Aoki, W. et al. 2009, ApJ, 698, 1803CrossRefGoogle Scholar
Asplund, M., Lambert, D. L., Nissen, P. E., Primas, F., & Smith, V. V. 2006, ApJ, 644, 229CrossRefGoogle Scholar
Asplund, M. & Meléndez, J. 2008, First Stars III, 990, 342Google Scholar
Boesgaard, A. M., Stephens, A., & Deliyannis, C. P. 2005, ApJ, 633, 398CrossRefGoogle Scholar
Bonifacio, P. et al. 2007, A&A, 462, 851Google Scholar
Casagrande, L., Ramírez, I., Meléndez, J., Bessell, M., & Asplund, M. 2010, A&A, submittedGoogle Scholar
Charbonnel, C. & Primas, F. 2005, A&A, 442, 961Google Scholar
Coc, A., Olive, K. A., Uzan, J.-P., & Vangioni, E. 2009, Phys. Rev. D., 79, 103512CrossRefGoogle Scholar
Cyburt, R. H., Fields, B. D., & Olive, K. A. 2008, J. Cosmology & Astro-Particle Phys., 11, 12CrossRefGoogle Scholar
Gustafsson, B., Edvardsson, B., Eriksson, K. et al. 2008, A&A, 486, 951Google Scholar
Hosford, A., Ryan, S. G., García Pérez, A. E., Norris, J. E., & Olive, K. A. 2009, A&A, 493, 601Google Scholar
Jedamzik, K. & Pospelov, M. 2009, New Journal of Physics, 11, 105028CrossRefGoogle Scholar
Kohri, K. & Santoso, Y. 2009, Phys. Rev. D., 79, 043514CrossRefGoogle Scholar
Korn, A. J. et al. 2006, Nature, 442, 657CrossRefGoogle Scholar
Lind, K., Primas, F., Charbonnel, C., Grundahl, F., & Asplund, M. 2009, A&A, 503, 545Google Scholar
Meléndez, J. & Ramírez, I. 2004, ApJ (Letters), 615, L33CrossRefGoogle Scholar
Meléndez, J., Asplund, M., Gustafsson, B., & Yong, D. 2009, ApJ (Letters), 704, L66CrossRefGoogle Scholar
Meléndez, J., Casagrande, L., Ramírez, I., & Asplund, M., & Schuster, W. J. 2010 A&A, submittedGoogle Scholar
Nissen, P. E., Akerman, C., Asplund, M., Fabbian, D., & Pettini, M. 2005, From Lithium to Uranium: Elemental Tracers of Early Cosmic Evolution, IAU Symp., 228, 101CrossRefGoogle Scholar
Ramírez, I., Allende Prieto, C., Redfield, S., & Lambert, D. L. 2006, A&A, 459, 613Google Scholar
Ramírez, I., Meléndez, J., & Asplund, M. 2009, A&A, 508, L17Google Scholar
Richard, O., Michaud, G., & Richer, J. 2005, ApJ, 619, 538CrossRefGoogle Scholar
Shi, J. R., Gehren, T., Zhang, H. W., Zeng, J. L., & Zhao, G. 2007, A&A, 465, 587Google Scholar
Spite, F. & Spite, M. 1982, A&A, 115, 357Google Scholar