PROGRESSIVE STAR FORMATION IN THE YOUNG GALACTIC SUPER STAR CLUSTER NGC 3603

Journal Article · Fri Sep 10 00:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/720/2/1108· OSTI ID:21460070

Beccari, Giacomo; Spezzi, Loredana; De Marchi, Guido; Andersen, Morten ^[1]; Paresce, Francesco ^[2]; Young, Erick ^[3]; Panagia, Nino; Bond, Howard ^[4]; Balick, Bruce ^[5]; Calzetti, Daniela ^[6]; Carollo, C Marcella ^[7]; Disney, Michael J ^[8]; Dopita, Michael A ^[9]; Frogel, Jay A ^[10]; Hall, Donald N. B. ^[11]; Holtzman, Jon A ^[12]; Kimble, Randy A ^[13]; McCarthy, Patrick J ^[14]; O'Connell, Robert W ^[15]; Saha, Abhijit ^[16]

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1. ESA, Space Science Department, Keplerlaan 1, 2200 AG Noordwijk (Netherlands)
2. INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, Via P. Gobetti, 101, I-40129 Bologna (Italy)
3. NASA-Ames Research Center, Moffett Field, CA 94035 (United States)
4. Space Telescope Science Institute, Baltimore, MD 21218 (United States)
5. Department of Astronomy, University of Washington, Seattle, WA 98195-1580 (United States)
6. Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)
7. Department of Physics, ETH-Zurich, 8093 Zurich (Switzerland)
8. School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom)
9. Research School of Astronomy and Astrophysics, The Australian National University, ACT 2611 (Australia)
10. Association of Universities for Research in Astronomy, Washington, DC 20005 (United States)
11. Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)
12. Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States)
13. NASA-Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
14. Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101-1292 (United States)
15. Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States)
16. National Optical Astronomy Observatories, Tucson, AZ 85726-6732 (United States)

Early Release Science observations of the cluster NGC 3603 with the WFC3 on the refurbished Hubble Space Telescope allow us to study its recent star formation history. Our analysis focuses on stars with H{alpha} 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 H{alpha} 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.

• OSTI ID: 21460070
• Journal Information: Astrophysical Journal, Vol. 720, Issue 2; Other Information: DOI: 10.1088/0004-637X/720/2/1108; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
EMISSION
SPATIAL DISTRIBUTION
STAR CLUSTERS
STARS
TELESCOPES
DISTRIBUTION