Hostname: page-component-745bb68f8f-hvd4g Total loading time: 0 Render date: 2025-01-21T21:12:01.077Z Has data issue: false hasContentIssue false
  • English
  • Français

Are the most metal-poor galaxies young?

Published online by Cambridge University Press:  01 August 2006

Daniel Kunth  and
Göran Östlin
Daniel Kunth
Affiliation:
Institut d'Astrophysique de Paris, 98bis Boulevard Arago, F75014 Paris, France email: [email protected]
Göran Östlin
Affiliation:
Stockholm observatory, AlbaNova University Center, 10691 Stockholm, Sweden email: [email protected]
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 review the possibility that metallicity could provide a diagnostic for the age of a galaxy, hence that the most metal-poor star forming galaxies in the local universe may be genuinely young. Indeed, observational evidence for “downsizing” shows the average age of the stars in a galaxy to decrease with decreasing mass and metallicity. However, we conclude both from observational and theoretical viewpoints that metallicity is not an arrow of time. Consequently the most metal–poor galaxies of our local universe are not necessarely young. Current observations suggest that an old stellar population is present in all metal-poor galaxies, although a couple of cases, e.g. IZw18, remain under debate. Further observations with more sentitive equipement should settle this question in the coming years.

Keywords

galaxies: abundancesdwarfevolution
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 2 , Symposium S235: Galaxy Evolution Across the Hubble Time , August 2006 , pp. 61 - 64
Copyright
Copyright © International Astronomical Union 2007

References

Aloisi, A., Tosi, M., & Greggio, L., 1999, AJ, 118, 302CrossRefGoogle Scholar
Bergvall, N., & Östlin, G., 1999, A&A, 390, 891Google Scholar
Bergvall, N., R”onnback, J., Masegosa, J., & Östlin, G., 1999, A&A, 341, 697Google Scholar
Cannon, J. M., Skillman, E. D., Sembach, K. R., & Bomans, D. J., 2005, ApJ, 618, 247Google Scholar
Cen, R., & Ostriker, J.P., 1999, ApJ, 519, L109CrossRefGoogle Scholar
Corbin, M., Vacca, W., Cid Fernandes, R., 2006, ApJ, in press.Google Scholar
Dufour, R. J., Garnett, D. R., Skillman, E. D., & Shields, G. A., 1996, Science with the Hubble Space Telescope — II, 348Google Scholar
Garnett, D. R., 2002, ApJ, 581, 1019Google Scholar
Grebel, E. K., Gallagher, J. S. III, & Harbeck, D., 2003, AJ, 125, 1926CrossRefGoogle Scholar
Hunter, D. A., & Thronson, H. A. Jr., 1995, ApJ, 452, 238CrossRefGoogle Scholar
Izotov, Y. I., & Thuan, T. X., 1999, ApJ, 511, 639Google Scholar
Izotov, Y. I., & Thuan, T. X., 2004, ApJ, 616, 768CrossRefGoogle Scholar
Izotov, Y. I., Stasińska, G., Meynet, G., Guseva, N. G., & Thuan, T. X., 2006, ApJ, 448, 955Google Scholar
Kunth, D., & "Ostlin, G., 2000, A&ARv, 10, 1Google Scholar
Kunth, D., & "Ostlin, G., 2001, ApSSS, 277, 281Google Scholar
Kunth, D., & Sargent, W. L. W., 1986, ApJ, 300, 496CrossRefGoogle Scholar
Lebouteiller, V., Kunth, D., Lequeux, J., Aloisi, A., Desert, J. -., Hebrard, G., Lecavelier des Etangs, A., & Vidal-Madjar, A., 2006, Astrophysics e-prints, astro-ph/0608445Google Scholar
Lequeux, J., Maucherat-Joubert, M., Deharveng, J. M., & Kunth, D., 1981, A&A, 103, 305Google Scholar
Lequeux, J., Peimbert, M.; Rayo, J. F.; Serrano, A.; & Torres-Peimbert, 1979, A&A, 80, 155Google Scholar
Momany, Y., 2005, ApJ, 439, 111Google Scholar
Östlin, G., Bergvall, N., & Roennback, J., 1998, A&A, 335, 85Google Scholar
Östlin, G., 2000, ApJ, 535, L99CrossRefGoogle Scholar
Östlin, G., & Mouhcine, M., 2005, A&A, 433, 979Google Scholar
Papaderos, P., Izotov, Y., Thuan, T., 2002, A&A, 393, 461Google Scholar
Pettini, M., 2006, ASP Conf. Ser., 353, 363Google Scholar
Rönnback, J., & Bergvall, N., 1995, A&A, 302, 353Google Scholar
Sargent, W. L. W., & Searle, L., 1970, ApJ, 162, L155CrossRefGoogle Scholar
Tremonti, C. A., 2004, ApJ, 613, 898CrossRefGoogle Scholar
van Zee, L., Salzer, J. J., & Haynes, M. P., 1998, ApJ, 497, L1CrossRefGoogle Scholar