Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-25T03:58:56.132Z Has data issue: false hasContentIssue false
  • English
  • Français

A new method to estimate the ages of globular clusters: the case of NGC 3201

Published online by Cambridge University Press:  01 October 2008

A. Calamida ,
G. Bono ,
P. B. Stetson ,
M. Dall'Ora ,
M. Monelli ,
C. E. Corsi ,
P. G. Prada Moroni ,
S. Degl'Innocenti ,
A. Dotter  and
C. Brasseur
...Show all authors
A. Calamida
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany email: [email protected]
G. Bono
Affiliation:
Universita' di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy INAF-Osservatorio Astronomico di Roma, Via Frascati 33, 00040, Monte Porzio Catone, Italy
P. B. Stetson
Affiliation:
DAO, HIA-NRC, 5071 W. Saanich Road, Victoria, BC V9E 2E7, Canada
M. Dall'Ora
Affiliation:
INAF-Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy
M. Monelli
Affiliation:
IAC - Instituto de Astrofisica de Canarias, Calle Via Lactea, E38200 La Laguna, Tenerife, Spain
C. E. Corsi
Affiliation:
INAF-Osservatorio Astronomico di Roma, Via Frascati 33, 00040, Monte Porzio Catone, Italy
P. G. Prada Moroni
Affiliation:
INAF-Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, 40131 Trieste, Italy
S. Degl'Innocenti
Affiliation:
INAF-Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, 40131 Trieste, Italy
A. Dotter
Affiliation:
UVIC, Victoria, BC V8W 3P6, Canada
C. Brasseur
Affiliation:
UVIC, Victoria, BC V8W 3P6, Canada
P. Amico
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany email: [email protected]
E. Marchetti
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany email: [email protected]
R. Buonanno
Affiliation:
Universita' di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
A. Di Cecco
Affiliation:
Universita' di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
S. D'Odorico
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany email: [email protected]
I. Ferraro
Affiliation:
INAF-Osservatorio Astronomico di Roma, Via Frascati 33, 00040, Monte Porzio Catone, Italy
G. Iannicola
Affiliation:
INAF-Osservatorio Astronomico di Roma, Via Frascati 33, 00040, Monte Porzio Catone, Italy
M. Nonino
Affiliation:
INAF-Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, 40131 Trieste, Italy
M. Romaniello
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München, Germany email: [email protected]
N. Sanna
Affiliation:
Universita' di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
D. A. Vandenberg
Affiliation:
UVIC, Victoria, BC V8W 3P6, Canada
M. Zoccali
Affiliation:
Universidad de Concepcion, Departamento de Fisica, Casilla 106-C, Concepcion, Chile
A. Walker
Affiliation:
Cerro Totolo Inter-American Observatory, Chile
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 devised a new method to estimate globular cluster absolute ages by adopting the knee of the bending of the lower main-sequence (MS) in the Near-Infrared (NIR) J, J - Ks color-magnitude diagram. The color difference between this feature and the Turn-Off point is strongly correlated to the cluster age. This method is marginally affected by distance and reddening uncertainties, and by the possible occurrence of differential reddening. Furthermore, the knee location does not depend on the cluster age and it is a robust theoretical prediction. We adopted accurate J, Ks-band photometry collected with both MAD/VLT and SOFI/NTT for the Galactic globular cluster NGC 3201 to identify the location of the knee at J~19.90 ±0.03 and J-Ks ~0.76±0.02 mag. The comparison with different sets of cluster isochrones, transformed adopting different Color–Temperature–Relations (CTRs), shows that the models are slightly redder than the observations for J > 19 mag. This difference could be due to the presence of a calibration drift or to a problem of the CTRs in this magnitude range.

Keywords

globular clusters: generalglobular clusters: individual (NGC 3201)
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 4 , Symposium S258: The Ages of Stars , October 2008 , pp. 189 - 196
Copyright
Copyright © International Astronomical Union 2009

References

Belokurov, V., et al. 2007, ApJ, 658, 337CrossRefGoogle Scholar
Bono, G., et al. 2008, ApJ, 686, L87CrossRefGoogle Scholar
Brott, I. & Hauschildt, P. H. 2005, ESASP, 576, 565Google Scholar
Buonanno, R., et al. 1998, ApJ, 501, L33CrossRefGoogle Scholar
Cardelli, J. A., Clayton, , & G. C., , Mathis, J. S. 1989, ApJ, 345, 245CrossRefGoogle Scholar
Cariulo, P., Degl'Innocenti, S., & Castellani, V. 2004, A&A 421, 1121Google Scholar
Casetti-Dinescu, D. I., et al. 2007, AJ, 134, 103CrossRefGoogle Scholar
Castellani, V. 1999, in Globular clusters, 10th Canary Islands Winter School of Astrophysics, 109CrossRefGoogle Scholar
Castellani, V. & Degl'Innocenti, S. 1999, A&A, 344, 97Google Scholar
Covey, K. R., et al. 2003, PASP, 115, 819CrossRefGoogle Scholar
Chaboyer, B. 1998, PhR, 307, 23Google Scholar
De, Angeli, et al. 2005, AJ, 130, 116Google Scholar
Dotter, A., et al. 2007, AJ, 134, 376CrossRefGoogle Scholar
Dotter, A., et al. 2008, ApJS, 178, 89CrossRefGoogle Scholar
Fitzpatrick, E. L. 1999, PASP, 111, 63CrossRefGoogle Scholar
Gilmozzi, R. & Spyromilio, J. 2007, Msngr, 127, 11Google Scholar
Gratton, R., Sneden, C., & Carretta, E. 2004, ARA&A, 42, 385Google Scholar
Grillmair, C. J. 2006, ApJ, 651, 29CrossRefGoogle Scholar
Harris, W. E. 2003, Catalog of Parameters for Milky Way Globular Clusters: The Database Hamilton: McMaster Univ., http://physun.physics.mcmaster.ca/~harris/mwgc.datGoogle Scholar
Kraft, R. & Ivans, I. 2003, PASP, 115, 143CrossRefGoogle Scholar
Layden, A. C. & Sarajedini, A. 2003, AJ, 125, 208CrossRefGoogle Scholar
Mazur, B., Krzemiski, W., & Thompson, I. B. 2003, MNRAS, 340, 1205CrossRefGoogle Scholar
Marchetti, E., et al. 2006, SPIE, 6272, 21Google Scholar
Piersimoni, A., Bono, G., & Ripepi, V. 2002, AJ, 124, 1528CrossRefGoogle Scholar
Pulone, L. et al. 1998, ApJ, 492, 41CrossRefGoogle Scholar
Pulone, L., De Marchi, G., & Paresce, F. 1999, A&A, 342, 440Google Scholar
Pritzl, B. J., Venn, K. A., & Irwin, M. 2005, AJ, 130, 2140CrossRefGoogle Scholar
Renzini, A. 1991, otci.conf., 131CrossRefGoogle Scholar
Rosenberg, A., et al. 1999, AJ, 118, 230CrossRefGoogle Scholar
Rutledge, , et al. 1997, PASP, 109, 907CrossRefGoogle Scholar
Saumon, D., et al. 1994, ApJ, 424, 333CrossRefGoogle Scholar
Saumon, D. & Marley, M. S. 2008, ApJ, 689, 1327CrossRefGoogle Scholar
Stetson, P. B. 1994, PASP, 106, 250CrossRefGoogle Scholar
Stetson, P. B., et al. 1999, AJ, 117, 247CrossRefGoogle Scholar
Stetson, P. B. 2005, PASP, 117, 563, http://www1.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/community/STETSON/standardsCrossRefGoogle Scholar
Vandenberg, D., Stetson, P. B., & Bolte, M. 1996, ARA&A, 34, 461Google Scholar
Vandenberg, D., et al. 2002, ApJ, 571, 487CrossRefGoogle Scholar
Vandenberg, D. & Clem, J. L. 2003, AJ, 126, 778CrossRefGoogle Scholar
Vandenberg, D., et al. 2008, ApJ, 675, 746CrossRefGoogle Scholar
van den Bergh, S. 1993, AJ, 105, 971CrossRefGoogle Scholar
Zoccali, M., et al. 2000, ApJ, 538, 289CrossRefGoogle Scholar
Zoccali, M., et al. 2003, A&A, 399, 931Google Scholar