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Multiple populations in the Sagittarius nuclear cluster M 54 and in other anomalous globular clusters

Published online by Cambridge University Press:  09 May 2016

A. P. Milone*
Affiliation:
Research School of Astronomy & Astrophysics, Australian National University, Mt Stromlo Observatory, via Cotter Rd, Weston, ACT 2611, Australia. email: milone@mso.anu.edu.au
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Abstract

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M 54 is the central cluster of the Sagittarius dwarf galaxy. This stellar system is now in process of being disrupted by the tidal interaction with the Milky Way and represents one of the building blocks of the Galactic Halo. Recent discoveries, based on the synergy of photometry and spectroscopy have revealed that the color-magnitude diagram (CMD) of some massive, anomalous, Globular Clusters (GCs) host stellar populations with different content of heavy elements. In this paper, I use multi-wavelength Hubble Space Telescope (HST) photometry to detect and characterize multiple stellar populations in M 54. I provide empirical evidence that this GC shares photometric and spectroscopic similarities with the class of anomalous GCs. These findings make it tempting to speculate that, similarly to Sagittarius nuclear cluster M 54, other anomalous GCs were born in an extra-Galactic environment.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2016 

References

Bellazzini, M., Ibata, R. A., Chapman, S. C., et al. 2008, AJ, 136, 1147CrossRefGoogle Scholar
Carretta, E., Bragaglia, A., Gratton, R., D'Orazi, V., & Lucatello, S. 2009, A&A, 508, 695Google Scholar
Carretta, E., Gratton, R. G., Lucatello, S., et al. 2010, ApJ, 722, L1CrossRefGoogle Scholar
Carretta, E., Bragaglia, A., Gratton, R. G., et al. 2010, ApJ, 714, L7CrossRefGoogle Scholar
Cassisi, S., Salaris, M., Pietrinferni, A., et al. 2008, ApJ, 672, L115CrossRefGoogle Scholar
D'Antona, F., Caloi, V., Montalbán, J., Ventura, P., & Gratton, R. 2002, A&A, 395, 69Google Scholar
D'Antona, F., Bellazzini, M., Caloi, V., et al. 2005, ApJ, 631, 868CrossRefGoogle Scholar
Da Costa, G. S., Held, E. V., Saviane, I., & Gullieuszik, M. 2009, ApJ, 705, 1481CrossRefGoogle Scholar
Gratton, R., Sneden, C., & Carretta, E. 2004, AA&A, 42, 385Google Scholar
Gratton, R. G., Carretta, E., & Bragaglia, A. 2012, A&AR, 20, 50Google Scholar
Johnson, C. I., Rich, R. M., Pilachowski, C. A., et al. 2015, AJ, 150, 63CrossRefGoogle Scholar
Lee, J.-W. 2015, ApJS, 219, 7CrossRefGoogle Scholar
Lim, D., Han, S.-I., Lee, Y.-W., et al. 2015, ApJS, 216, 19CrossRefGoogle Scholar
Marino, A. F., Villanova, S., Piotto, G., et al. 2008, A&A, 490, 625Google Scholar
Marino, A. F., Milone, A. P., Piotto, G., et al. 2009, A&A, 505, 1099Google Scholar
Marino, A. F., Sneden, C., Kraft, R. P., et al. 2011, A&A, 532, A8Google Scholar
Marino, A. F., Milone, A. P., Piotto, G., et al. 2011, ApJ, 731, 64CrossRefGoogle Scholar
Marino, A. F., Milone, A. P., Sneden, C., et al. 2012, A&A, 541, A15Google Scholar
Marino, A. F., Milone, A. P., Karakas, A. I., et al. 2015, MNRAS, 450, 815CrossRefGoogle Scholar
McLaughlin, D. E. & van der Marel, R. P. 2005, ApJS, 161, 304CrossRefGoogle Scholar
Milone, A. P., Bedin, L. R., Piotto, G., et al. 2008, ApJ, 673, 241CrossRefGoogle Scholar
Milone, A. P., Piotto, G., Bedin, L. R., et al. 2012, ApJ, 744, 58CrossRefGoogle Scholar
Milone, A. P., Marino, A. F., Piotto, G., et al. 2013, ApJ, 767, 120CrossRefGoogle Scholar
Milone, A. P., Marino, A. F., Dotter, A., et al. 2014, ApJ, 785, 21CrossRefGoogle Scholar
Milone, A. P., Marino, A. F., Piotto, G., et al. 2015, ApJ, 808, 51CrossRefGoogle Scholar
Milone, A. P., Marino, A. F., Piotto, G., et al. 2015, MNRAS, 447, 927CrossRefGoogle Scholar
Monaco, L., Bellazzini, M., Bonifacio, P., et al. 2005, A&A, 441, 141Google Scholar
Piotto, G., Bedin, L. R., Anderson, J., et al. 2007, ApJ, 661, L53CrossRefGoogle Scholar
Piotto, G., Milone, A. P., Anderson, J., et al. 2012, ApJ, 760, 39CrossRefGoogle Scholar
Piotto, G., Milone, A. P., Bedin, L. R., et al. 2015, AJ, 149, 91CrossRefGoogle Scholar
Sarajedini, A. & Layden, A. C. 1995, AJ, 109, 1086CrossRefGoogle Scholar
Sbordone, L., Salaris, M., Weiss, A., & Cassisi, S. 2011, A&A, 534, A9Google Scholar
Siegel, M. H., Dotter, A., Majewski, S. R., et al. 2007, ApJ, 667, L57CrossRefGoogle Scholar
Ventura, P., Caloi, V., D'Antona, F., et al. 2009, MNRAS, 399, 934CrossRefGoogle Scholar
Villanova, S., Geisler, D., & Piotto, G. 2010, ApJ, 722, L18CrossRefGoogle Scholar
Yong, D., Grundahl, F., Johnson, J. A., & Asplund, M. 2008, ApJ, 684, 1159CrossRefGoogle Scholar
Yong, D. & Grundahl, F. 2008, ApJ, 672, L29CrossRefGoogle Scholar
Yong, D., Grundahl, F., D'Antona, F., et al. 2009, ApJ, 695, L62CrossRefGoogle Scholar
Yong, D., Roederer, I. U., Grundahl, F., et al. 2014, MNRAS, 441, 3396CrossRefGoogle Scholar
Yong, D., Grundahl, F., & Norris, J. E. 2015, MNRAS, 446, 3319CrossRefGoogle Scholar