Progressive star formation in the young galactic super star cluster NGC 3603
Abstract
Early release science observations of the cluster NGC3603 with the WFC3 on the refurbished HST allow us to study its recent star formation history. Our analysis focuses on stars with Halpha excess emission, a robust indicator of their pre-main sequence (PMS) accreting status. The comparison with theoretical PMS isochrones shows that 2/3 of the objects with Halpha excess emission have ages from 1 to 10 Myr, with a median value of 3 Myr, while a surprising 1/3 of them are older than 10 Myr. The study of the spatial distribution of these PMS stars allows us to confirm their cluster membership and to statistically separate them from field stars. This result establishes unambiguously for the first time that star formation in and around the cluster has been ongoing for at least 10-20 Myr, at an apparently increasing rate.
Keywords
Cite
@article{arxiv.1007.2795,
title = {Progressive star formation in the young galactic super star cluster NGC 3603},
author = {Giacomo Beccari and Loredana Spezzi and Guido De Marchi and Francesco Paresce and Erick Young and Morten Andersen and Nino Panagia and Bruce Balick and Howard Bond and Daniela Calzetti and C. Marcella Carollo and Michael J. Disney and Michael A. Dopita and Jay A. Frogel and Donald N. B. Hall and Jon A. Holtzman and Randy A. Kimble and Patrick J. McCarthy and Robert W. O'Connell and Abhijit Saha and Joseph I. Silk and John T. Trauger and Alistair R. Walker and Bradley C. Whitmore and Rogier A. Windhorst},
journal= {arXiv preprint arXiv:1007.2795},
year = {2015}
}
Comments
10 pages, 8 figures, accepted for publication in The Astrophysical Journal