Absolute-Magnitude Calibration for Red Giants Based on Colour–Magnitude Diagrams of Galactic Clusters: I. Calibration in V and B – V
S. Karaali A B , S. Bilir A and E. Yaz Gökçe AA Istanbul University, Faculty of Sciences, Department of Astronomy and Space Sciences, 34119, Istanbul, Turkey
B Corresponding author. Email: karsa@istanbul.edu.tr
Publications of the Astronomical Society of Australia 29(4) 509-522 https://doi.org/10.1071/AS12003
Submitted: 9 January 2012 Accepted: 17 April 2012 Published: 31 May 2012
Abstract
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 metallicity 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.
Keywords: stars: distances — globular clusters: individual (M92, M13, M5, 47 Tuc) — open clusters: individual (M67, NGC 6791)
References
Alonso, M. V., Salaris, M., Martinez-Roger, C., Straniero, O. and Arribas, S., 1997, A&A, 323, 374| 1:CAS:528:DyaK2sXkvFKgurw%3D&md5=92fd2936231bd1f70857029d319150a9CAS |
Breddels, M. A. et al., 2010, A&A, 511, 90
Buonanno, R., Corsi, C. E., Pulone, L., Pecci, F. F., Richer, H. B. and Fahlman, G. C., 1995, AJ, 109, 663
Chen, B. et al., 2001, ApJ, 553, 184
| Crossref | GoogleScholarGoogle Scholar |
Gratton, R. G., Fusi Pecci, F., Carretta, E., Clementini, G., Corsi, C. E. and Lattanzi, M., 1997, ApJ, 491, 749
| Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXktFamtg%3D%3D&md5=7f8b71f6441f13e19b3f688fb2b5ddbbCAS |
Harris, W. E., 1996, AJ, 112, 1487
Harris, W. E., 2010, arXiv:astro-ph/1012.3224
Hesser, J. E., Harris, W. E., Vandenberg, D. A., Allwright, J. W. B., Shott, P. and Stetson, P. B., 1987, PASP, 99, 739
| Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2sXmtVyisb0%3D&md5=547550fc4b4d3defb3eef9de535daeadCAS |
Hodder, P. J. C., Nemec, J. M., Richer, H. B. and Fahlman, G. G., 1992, AJ, 103, 460
Hog, E. and Flynn, C., 1998, MNRAS, 294, 28
| Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXhslCjtbY%3D&md5=9dade1e89d7be5465f9b769ff8c248ecCAS |
Karaali, S., Karataş, Y., Bilir, S., Ak, S. G. and Hamzaoğlu, E., 2003, PASA, 20, 270
| Crossref | GoogleScholarGoogle Scholar |
Laird, J. B., Carney, B. W. and Latham, D. W., 1988, AJ, 96, 1908
| 1:CAS:528:DyaL1MXksl2lsA%3D%3D&md5=182524489caaea4ae9a6f055850f31dbCAS |
Ljunggren, B. and Oja, T., 1966, IAUS, 24, 317
Marigo, P., Girardi, L., Bressan, A., Groenewegen, M. A. T., Silva, L. and Granato, G. L., 2008, A&A, 482, 883
| 1:CAS:528:DC%2BD1cXosFGrt7Y%3D&md5=15b6f7fab544d4f3e24923cac965d36eCAS |
McClure, R. D., 1976, AJ, 81, 182
Meibom, S. et al., 2009, AJ, 137, 5086
| 1:CAS:528:DC%2BD1MXnsVCrtrs%3D&md5=6789b939eeef58aeac532c94ab7fd622CAS |
Nissen, P. E. and Schuster, W. J., 1991, A&A, 251, 457
Percival, S. M., Salaris, M., van Wyk, F. and Kilkenny, D., 2002, ApJ, 573, 174
| Crossref | GoogleScholarGoogle Scholar |
Perryman, M. A. C. et al., 1997, A&A, 323, L49
Phleps, S., Meisenheimer, K., Fuchs, B. and Wolf, C., 2000, A&A, 356, 108
| 1:CAS:528:DC%2BD3cXjsFaltLo%3D&md5=4d0c4d19ab6cc963f54c4cd19b3338fbCAS |
Rey, S.-C., Lee, Y.-W., Byun, Y.-I. & Chun, M.-S., 1998, AJ, 116, 1775
Salaris, M. and Weiss, A., 2002, A&A, 388, 492
Sandage, A., 1970, ApJ, 162, 841
| Crossref | GoogleScholarGoogle Scholar |
Sandage, A., Lubin, L. M. and VandenBerg, D. A., 2003, PASP, 115, 1187
| Crossref | GoogleScholarGoogle Scholar |
Sandquist, E. L., Bolte, M., Stetson, P. B. and Hesser, J. E., 1996, ApJ, 470, 910
| Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XmvFKls7o%3D&md5=6a9406eb8f940c6d92cbad9f3fe548c8CAS |
Santos, J. F. C. and Piatti, A. E., 2004, A&A, 428, 79
| 1:CAS:528:DC%2BD2MXmsF2nsQ%3D%3D&md5=2afe8d2796bdc17bdb1c569e62cfd275CAS |
Sarajedini, A., 1993, AJ, 105, 2172
Siegel, M. H., Majewski, S. R., Reid, I. N. and Thompson, I. B., 2002, ApJ, 578, 151
| Crossref | GoogleScholarGoogle Scholar |
Steinmetz, M. et al., 2006, AJ, 132, 1645
| 1:CAS:528:DC%2BD28XhtFyhsbzN&md5=8c804760f8518bf74b368c76f6224b6aCAS |
Stetson, P. B. and Harris, W. E., 1988, AJ, 96, 909
| 1:CAS:528:DyaL1cXltlynsbo%3D&md5=856533662ec95a00e9b56c2816c7f39dCAS |
VandenBerg, D. A., Bergbusch, P. A. and Dowler, P. D., 2006, ApJS, 162, 375
| Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xis1ars7o%3D&md5=019dd0efe6bfc58729793d75b7fc1ef1CAS |
Zinn, R. and West, M. J., 1984, ApJS, 55, 45
| Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2cXitFylsLs%3D&md5=0419d4a1855235a13c92da3a18e06a33CAS |
Zwitter, T. et al., 2010, A&A, 522A, 54