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Observational problems in determining the ages of open clusters

Published online by Cambridge University Press:  01 October 2008

Elizabeth J. Jeffery
Elizabeth J. Jeffery*
Affiliation:
Department of Astronomy, The University of Texas at Austin, Austin, TX 78712, USA email: [email protected]
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Abstract

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Open clusters have long been objects of interest in astronomy. As a good approximation of essentially pure stellar populations, they have proved very useful for studies in a wide range of astrophysically interesting questions, including stellar evolution and atmospheres, the chemical and dynamical evolution of our Galaxy, and the structure of our Galaxy. Of fundamental importance to our understanding of open clusters is accurate determinations of cluster ages. Currently there are two main techniques for independently determining the ages of stellar populations: main sequence evolution theory (via cluster isochrones) and white dwarf cooling theory. We will provide an overview of these two methods, the current level of agreement between them, as well as a look to the current state of increasing precision in the determination of each. Particularly I will discuss the comprehensive data set collection that is being done by the WIYN Open Cluster Study, as well as a new Bayesian statistical technique that has been developed by our group and its applications in improving and determining white dwarf ages of open clusters. I will review the so-called bright white dwarf technique, a new way of measuring cluster ages with just the bright white dwarfs. I will discuss the first application of the Bayesian technique to the Hyades, also demonstrating the first successful application of the bright white dwarf technique. These results bring the white dwarf age of the Hyades into agreement with the main sequence turn off age for the first time.

Keywords

open clusters and associations: generalwhite dwarfs
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 4 , Symposium S258: The Ages of Stars , October 2008 , pp. 141 - 152
Copyright
Copyright © International Astronomical Union 2009

References

Bergeron, P., Wesemael, F., & Beauchamp, A. 1995, pasp, 107, 1047CrossRefGoogle Scholar
Chaboyer, B., Demarque, P., & Sarajedini, A. 1996, ApJ, 459, 558CrossRefGoogle Scholar
Claver, C. F. 1995, PhD. Thesis, The University of Texas at AustinGoogle Scholar
DeGennaro, S., von Hippel, T., Jefferys, W. H., Stein, N., van Dyk, D., & Jeffery, E. J., ApJ, in pressGoogle Scholar
Dotter, A., Chaboyer, B., Jevremovic, D., Kostov, V., Baron, E., & Ferguson, J. W. 2008, ApJS, in press, arXiv:0804.4473Google Scholar
Frommhold, L. 1993, Collision-Induced Absorption in Gases (Cambridge: Cambridge Univ. Press)CrossRefGoogle Scholar
Geller, A. M., Mathieu, R. D., Harris, H. C., & McClure, R. D. 2008, AJ, 135, 2264CrossRefGoogle Scholar
Girardi, L., Bressan, A., Bertelli, G., & Chiosi, C. 2000, A&AS, 141, 371Google Scholar
Hartnick, F. D. A., Hesser, J. E., & McClure, R. D. 1972, ApJ, 174, 554Google Scholar
Hernandez, X. & Valls-Gabaud, D. 2008, MNRAS, 383, 1603CrossRefGoogle Scholar
Isern, J., Garca-Berro, E., Hernanz, M., & Chabrier, G. 2000, ApJ, 528, 397CrossRefGoogle Scholar
Jeffery, E. J., von Hippel, T., Jefferys, W. H., Winget, D. E., Stein, N., & DeGennaro, S. 2007, ApJ, 658, 391CrossRefGoogle Scholar
Kafka, S. & Honeycutt, R. K. 2003, AJ, 126, 276CrossRefGoogle Scholar
Kilic, M., von Hippel, T., Mullally, F., Reach, W. T., Kuchner, M. J., Winget, D. E., & Burrows, A. 2006, ApJ, 642, 1051CrossRefGoogle Scholar
Mestel, L. 1952, MNRAS, 112, 583CrossRefGoogle Scholar
Metcalfe, T. S., Montgomery, M. H., & Kanaan, A. 2004, ApJ, 605, L133CrossRefGoogle Scholar
Miller, G. E. & Scalo, J. M. 1979, ApJS, 41, 513CrossRefGoogle Scholar
Paulson, D. B., Sneden, C., & Cochran, W. D. 2003, AJ, 125, 3185CrossRefGoogle Scholar
Perryman, M. A. C. et al. 1998, A&A, 331, 81Google Scholar
Platais, I., Kozhurina-Platais, V., Mathieu, R. D., Girard, T. M., & van Altena, W. F. 2003, AJ, 126, 2922CrossRefGoogle Scholar
Sarajedini, A., von Hippel, T., Kozhurina-Platais, V., & Demarque, P. 1999, AJ, 118, 2894CrossRefGoogle Scholar
Steinhauer, A. & Deliyannis, C. P. 2004, ApJ, 614, 65CrossRefGoogle Scholar
Taylor, B. J. & Joner, M. D. 2005, ApJS, 159, 100CrossRefGoogle Scholar
Tosi, M., Greggio, L., Marconi, G., & Focardi, P. 1991 AJ, 102, 951CrossRefGoogle Scholar
Tosi, M., Bragaglia, A., & Cignoni, M. 2007, MNRAS, 378, 730CrossRefGoogle Scholar
von Hippel, T., Gilmore, G., & Jones, D. H. P. 1995, MNRAS, 273, L39CrossRefGoogle Scholar
von Hippel, T. 2005, ApJ, 622, 565CrossRefGoogle Scholar
von Hippel, T., Jefferys, W. H., Scott, J., Stein, N., Winget, D. E., DeGennaro, S., Dam, A., & Jeffery, E. J. 2006, ApJ, 645, 1436CrossRefGoogle Scholar
Winget, D. E., Hansen, C. J., Liebert, J., van Horn, H. M., Fontaine, G., Nather, R. E., Kepler, S. O., & Lamb, D. Q. 1987, ApJ, 315, L77CrossRefGoogle Scholar
Weidemann, V., Jordan, S., Iben, I. J., & Casertano, S. 1992, AJ, 104, 1876CrossRefGoogle Scholar
Weidemann, V. 2000, A&A, 363, 647Google Scholar
Wood, M. A. 1992, ApJ, 386, 539CrossRefGoogle Scholar
Yi, S., Demarque, P., Kim, Y.-C., Lee, Y.-W., Ree, C. H., Lejeune, T., & Barnes, S. 2001, ApJS, 136, 417CrossRefGoogle Scholar