Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-20T00:30:29.143Z Has data issue: false hasContentIssue false

Absolute-Magnitude Calibration for Red Giants Based on Colour–Magnitude Diagrams of Galactic Clusters: I. Calibration in V and B–V

Published online by Cambridge University Press:  02 January 2013

S. Karaali*
Affiliation:
Istanbul University, Faculty of Sciences, Department of Astronomy and Space Sciences, 34119, Istanbul, Turkey
S. Bilir
Affiliation:
Istanbul University, Faculty of Sciences, Department of Astronomy and Space Sciences, 34119, Istanbul, Turkey
E. Yaz Gökçe
Affiliation:
Istanbul University, Faculty of Sciences, Department of Astronomy and Space Sciences, 34119, Istanbul, Turkey
*
BCorresponding author. 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 present an absolute-magnitude calibration for red giants using the colour–magnitude diagrams of six Galactic clusters with different metallicities: M92, M13, M5, 47 Tuc, M67 and NGC 6791. The combination of the absolute magnitude offset from the fiducial of giant sequence of the cluster M5 with the corresponding metallicity offset provides a calibration estimation for the absolute magnitude of red giants for a given (B – V)0 colour. The calibration is defined in the colour interval 0.75 ≤ (B – V)0 ≤ 1.50 mag and it covers the metal licity interval −2.15 > [Fe/H]≤+0.37 dex. 91% of the absolute magnitude residuals obtained by the application of the procedure to another set of Galactic clusters lie in the interval −0.40 < ΔM≤+0.40 mag. The mean and the standard deviation of the residuals are 0.05 and 0.19 mag, respectively. We fitted the absolute magnitude also to metallicity and age for a limited sub-sample of (B – V)0 colour, just to test the effect of age in absolute-magnitude calibration. Comparison of the mean and the standard deviation of the residuals evaluated by this procedure with the corresponding ones provided by the procedure where the absolute magnitude fitted to a third degree polynomial of metallicity show that the age parameter may be omitted in absolute magnitude estimation of red giants. The derived relations are applicable to stars older than 4 Gyr, the age of the youngest calibrating cluster.

Type
Regular Papers
Copyright
Copyright © Astronomical Society of Australia 2012

References

Alonso, M. V., Salaris, M., Martinez-Roger, C., Straniero, O. & Arribas, S., 1997, A&A, 323, 374Google Scholar
Bred dels, M. A., et al. , 2010, A&A, 511, 90Google Scholar
Buonanno, R., Corsi, C. E., Pulone, L., Pecci, F. F., Richer, H. B. & Fahlman, G. C., 1995, AJ, 109, 663CrossRefGoogle Scholar
Chen, B., et al. , 2001, ApJ, 553, 184CrossRefGoogle Scholar
Gratton, R. G., Fusi Pecci, F., Carretta, E., Clementini, G., Corsi, C. E. & Lattanzi, M., 1997, ApJ, 491, 749CrossRefGoogle Scholar
Harris, W. E., 1996, AJ, 112, 1487CrossRefGoogle Scholar
Harris, W. E., 2010, arXiv:astro-ph/1012.3224Google Scholar
Hesser, J. E., Harris, W. E., Vandenberg, D. A., Allwright, J. W. B., Shott, P. & Stetson, P. B., 1987, PASP, 99, 739CrossRefGoogle Scholar
Hodder, P. J. C., Nemec, J. M., Richer, H. B. & Fahlman, G. G., 1992, AJ, 103, 460CrossRefGoogle Scholar
Hog, E. & Flynn, C., 1998, MNRAS, 294, 28CrossRefGoogle Scholar
Karaali, S., Karataş, Y., Bilir, S., Ak, S. G. & Hamzaogğlu, E., 2003, PASA, 20, 270CrossRefGoogle Scholar
Laird, J. B., Carney, B. W. & Latham, D. W., 1988, AJ, 96, 1908CrossRefGoogle Scholar
Ljunggren, B. & Oja, T., 1966, IAUS, 24, 317Google Scholar
Marigo, P., Girardi, L., Bressan, A., Groenewegen, M. A. T., Silva, L. & Granato, G. L., 2008, A&A, 482, 883Google Scholar
McClure, R. D., 1976, AJ, 81, 182CrossRefGoogle Scholar
Meibom, S., et al. , 2009, AJ, 137, 5086CrossRefGoogle Scholar
Nissen, P. E. & Schuster, W. J., 1991, A&A, 251, 457Google Scholar
Percival, S. M., Salaris, M., van Wyk, F. & Kilkenny, D., 2002, ApJ, 573, 174CrossRefGoogle Scholar
Perryman, M. A. C., et al. , 1997, A&A, 323, L49Google Scholar
Phleps, S., Meisenheimer, K., Fuchs, B. & Wolf, C., 2000, A&A, 356, 108Google Scholar
Rey, S.-C., Lee, Y.-W., Byun, Y.-I. & Chun, M.-S., 1998, AJ, 116, 1775CrossRefGoogle Scholar
Salaris, M. & Weiss, A., 2002, A&A, 388, 492Google Scholar
Sandage, A., 1970, ApJ, 162, 841CrossRefGoogle Scholar
Sandage, A., Lubin, L. M. & VandenBerg, D. A., 2003, PASP, 115, 1187CrossRefGoogle Scholar
Sandquist, E. L., Bolte, M., Stetson, P. B. & Hesser, J. E., 1996, ApJ, 470, 910CrossRefGoogle Scholar
Santos, J. F. C. Jr., & Piatti, A. E., 2004, A&A, 428, 79Google Scholar
Sarajedini, A., 1993, AJ, 105, 2172CrossRefGoogle Scholar
Siegel, M. H., Majewski, S. R., Reid, I. N. & Thompson, I. B., 2002, ApJ, 578, 151CrossRefGoogle Scholar
Steinmetz, M., et al. , 2006, AJ, 132, 1645CrossRefGoogle Scholar
Stetson, P. B. & Harris, W. E., 1988, AJ, 96, 909CrossRefGoogle Scholar
VandenBerg, D. A., Bergbusch, P. A. & Dowler, P. D., 2006, ApJS, 162, 375CrossRefGoogle Scholar
Zinn, R. & West, M. J., 1984, ApJS, 55, 45CrossRefGoogle Scholar
Zwitter, T., et al. , 2010, A&A, 522A, 54Google Scholar