Multiple stellar populations in the globular cluster M3 (NGC 5272): a Strömgren perspective
Abstract
We present Strömgren photometry of the Galactic Globular Cluster M3 to study its multiple generations phenomenon. The use of different colour-magnitude diagrams (CMDs) and especially of the notoriously efficient cy index allowed us to detect a double red giant branch in the cluster CMD. After decontamination from fore- and background sources, the two sequences turned out to be equally populated. The two components also show a bimodal radial distribution well corresponding to that predicted by numerical simulations for clusters living in an intermediate dynamical evolutive state and with a population with modified chemical composition that was born more centrally concentrated than the primordial. The analysis of high-resolution spectra quantitatively demonstrates that the two detected sequences correspond to the first (Na-poor) generation and the second (Na-rich) generation, thus confirming the importance of synergy between photometry and spectroscopy.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- June 2016
- DOI:
- 10.1093/mnras/stw583
- arXiv:
- arXiv:1603.02827
- Bibcode:
- 2016MNRAS.458.4162M
- Keywords:
-
- techniques: photometric;
- stars: abundances;
- Hertzsprung-Russell and colour-magnitude diagrams;
- stars: Population II;
- globular clusters: general;
- globular clusters: individual: ngc5272;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 11 pages, 9 figures, 2 tables. Accepted for publication in MNRAS