Skip to main content Accessibility help
×
Home
Hostname: page-component-888d5979f-l84fh Total loading time: 0.182 Render date: 2021-10-26T11:58:33.057Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": true, "newCiteModal": false, "newCitedByModal": true, "newEcommerce": true, "newUsageEvents": true }

Lithium in a metal-poor external galaxy: ω Centauri

Published online by Cambridge University Press:  23 April 2010

P. Bonifacio
Affiliation:
GEPI, Observatoire de Paris, CNRS, Université Paris Diderot; Place Jules Janssen, 92190 Meudon, France email: Piercarlo.Bonifacio@obspm.fr Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Trieste, Via Tiepolo 11, I-34143 Trieste, Italy
L. Monaco
Affiliation:
Universidad de Concepción, Casilla 160-C, Concepción, Chile European Southern Observatory, Casilla 19001, Santiago, Chile
L. Sbordone
Affiliation:
Max Planck Institut for Astrophysics Karl-Schwarzschild-Str. 1 85741 Garching, Germany
S. Villanova
Affiliation:
Universidad de Concepción, Casilla 160-C, Concepción, Chile
E. Pancino
Affiliation:
Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127, Bologna, Italy
Rights & Permissions[Opens in a new window]

Abstract

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

ω Centauri is a massive stellar system which is currently going through the Galactic Halo. Its compact aspect and spheroidal shape have for a long time led to it being classified as a Globular Cluster. However the fact that its stars cover a wide metallicity range (−0.6 < [Fe/H] < −2.1), points to this object as an external galaxy, satellite of the Milky Way. Lithium among warm metal-poor stars shows a roughly constant abundance, the “Spite Plateau”. This has been interpreted as evidence for a primordial origin of the lithium nucleus, at the time of nucleosynthesis. After the physical conditions under which nucleosynthesis occurred, have been constrained by the observations of the fluctuations of the Cosmic Microwave Background, we are facing a “cosmological lithium problem”, namely the primordial lithium was a factor of three to four higher than what observed in the Spite plateau. Several avenues may be taken to solve this conundrum, either relying on fundamental physics or on stellar physics, however the realm of possibilities may be considerably narrowed by observing stellar populations in different galaxies, which have experienced different evolutionary histories. Some of the proposed “solutions” may be clearly ruled out, depending on the observation of lithium in the metal-poor populations of external galaxies. ω Centauri is the only external galaxy amenable to such an investigation in the era of 8m telescopes. We have pushed to its limits FLAMES at the ESO 8.2m telescope to obtain high resolution spectra of the Li i doublet in 91 Turn-Off and Sub-Giant stars at V ~ 18 in ω Centauri. We present our preliminary results on this data which suggest that the Li content in ω Centauri warm stars is comparable to that observed in Galactic Halo field stars of similar metallicities and temperatures. This may effectively rule out a whole class of models which invoke a severe Li depletion through processing of material in an early generation of massive stars.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2010

References

Barklem, P. S., Piskunov, N., & O'Mara, B. J. 2000a, A&A (Letters), 355, 5Google Scholar
Barklem, P. S., Piskunov, N., & O'Mara, B. J. 2000b, A&A, 363, 1091Google Scholar
Bellini, A., Piotto, G., Bedin, L.R., Anderson, J., Platais, I. et al. 2009, A&A, 493, 959Google Scholar
Bonifacio, P. et al. 2002, A&A, 390, 91Google Scholar
Cayrel, R. 1988, in The Impact of Very High S/N Spectroscopy on Stellar Physics, G. Cayrel de Strobel and M. Spite eds., IAU Symp. 132, p. 345Google Scholar
D'Antona, F. & Ventura, P. 2010, this volumeGoogle Scholar
Dunkley, J. et al. 2009, ApJS, 180, 306CrossRefGoogle Scholar
Hilker, M., Kayser, A., Richtler, T., & Willemsen, P. 2004, A&A (Letters), 422, 9Google Scholar
Hisano, J., Kawasaki, M., Kohri, K., & Nakayama, K. 2009, Phys. Rev. D, 79, 063514CrossRefGoogle Scholar
Hughes, J., Wallerstein, G., van Leeuwen, F., & Hilker, M. 2004, AJ, 127, 980CrossRefGoogle Scholar
Jedamzik, K. 2004, Phys. Rev. D, 70, 083510CrossRefGoogle Scholar
Jedamzik, K. 2006, Phys. Rev. D, 74, 103509CrossRefGoogle Scholar
Jittoh, T. et al. 2008, Phys. Rev. D, 78, 055007CrossRefGoogle Scholar
Johnson, C. I., Pilachowski, C. A., Michael Rich, R., & Fulbright, J. P. 2009, ApJ, 698, 2048CrossRefGoogle Scholar
Kayser, A., Hilker, M., Richtler, T., & Willemsen, P. G. 2006, A&A, 458, 777Google Scholar
Kurucz, R. L. 2005, Memorie della Società Astronomica Italiana Supplementi, 8, 14Google Scholar
Lee, Y.-W. et al. 2005, ApJ (Letters), 621, 57CrossRefGoogle Scholar
Norris, J. E. 2004, ApJ (Letters), 612, 25CrossRefGoogle Scholar
Piau, L. et al. 2006, ApJ, 653, 300CrossRefGoogle Scholar
Richard, O., Michaud, G., & Richer, J. 2005, ApJ, 619, 538CrossRefGoogle Scholar
Romano, D., Tosi, M., Cignoni, M., Matteucci, F., Pancino, E., & Bellazzini, M. 2009, MNRAS, 1604Google Scholar
Sbordone, L. 2005, Memorie della Societa Astronomica Italiana Supplementi, 8, 61Google Scholar
Sbordone, L., Bonifacio, P., Castelli, F., & Kurucz, R. L. 2004, Memorie della Societá Astronomica Italiana Supplementi, 5, 93Google Scholar
Sbordone, et al. 2010, A&A submittedGoogle Scholar
Schaller, G., Schaerer, D., Meynet, G., & Maeder, A. 1992, A&AS, 96, 269Google Scholar
Sollima, A., Ferraro, F. R., Pancino, E., & Bellazzini, M. 2005, MNRAS, 357, 265CrossRefGoogle Scholar
Spite, M. & Spite, F. 1982a, Nature, 297, 483CrossRefGoogle Scholar
Spite, F. & Spite, M. 1982b, A&A, 115, 357Google Scholar
Spite, M. & Spite, F. 2010, IAU Symposium 268: “Light elements in the Universe”, Charbonnel, C., Tosi, M., Primas, F. & Chiappini, C., eds., this volumeGoogle Scholar
Steigman, G. 2010, IAU Symposium 268: “Light elements in the Universe”, Charbonnel, C., Tosi, M., Primas, F. & Chiappini, C., eds., this volumeGoogle Scholar
Stanford, L. M., Da Costa, G. S., Norris, J. E., & Cannon, R. D. 2006, ApJ, 647, 1075CrossRefGoogle Scholar
Stehle, R. & King, A. R. 1999, MNRAS, 304, 698CrossRefGoogle Scholar
van de Ven, G., van den Bosch, R. C. E., Verolme, E. K., & de Zeeuw, P. T. 2006, A&A, 445, 513Google Scholar
Ventura, P. & D'Antona, F. 2010, MNRAS, in press, arXiv:0912.4399Google Scholar
Villanova, S. et al. 2007, ApJ, 663, 296CrossRefGoogle Scholar
You have Access

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Lithium in a metal-poor external galaxy: ω Centauri
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Lithium in a metal-poor external galaxy: ω Centauri
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Lithium in a metal-poor external galaxy: ω Centauri
Available formats
×
×

Reply to: Submit a response

Please enter your response.

Your details

Please enter a valid email address.

Conflicting interests

Do you have any conflicting interests? *