STAR FORMATION IN 30 DORADUS
- European Space Agency, Space Science Department, Keplerlaan 1, 2200 AG Noordwijk (Netherlands)
- Istituto di Astrofisica Spaziale e Fisica Cosmica, Via Gobetti 101, 40129 Bologna (Italy)
- Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
- European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching (Germany)
- Department of Astronomy, University of Washington, Seattle, WA 98195-1580 (United States)
- Mount Stromlo and Siding Spring Observatories, Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia)
- Galaxies Unlimited, 8726 Hickory Bend Trail, Potomac, MD 20854 (United States)
- Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)
- Department of Physics, ETH-Zurich, Zurich 8093 (Switzerland)
- School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom)
- Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
- Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States)
- NASA-Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
Using observations obtained with the Wide-Field Camera 3 on board the Hubble Space Telescope, we have studied the properties of the stellar populations in the central regions of 30 Dor in the Large Magellanic Cloud. The observations clearly reveal the presence of considerable differential extinction across the field. We characterize and quantify this effect using young massive main-sequence stars to derive a statistical reddening correction for most objects in the field. We then search for pre-main-sequence (PMS) stars by looking for objects with a strong (>4{sigma}) H{alpha} excess emission and find about 1150 of them over the entire field. Comparison of their location in the Hertzsprung-Russell diagram with theoretical PMS evolutionary tracks for the appropriate metallicity reveals that about one-third of these objects are younger than {approx}4 Myr, compatible with the age of the massive stars in the central ionizing cluster R 136, whereas the rest have ages up to {approx}30 Myr, with a median age of {approx}12 Myr. This indicates that star formation has proceeded over an extended period of time, although we cannot discriminate between an extended episode and a series of short and frequent bursts that are not resolved in time. While the younger PMS population preferentially occupies the central regions of the cluster, older PMS objects are more uniformly distributed across the field and are remarkably few at the very center of the cluster. We attribute this latter effect to photo-evaporation of the older circumstellar disks caused by the massive ionizing members of R 136.
- OSTI ID:
- 21587529
- Journal Information:
- Astrophysical Journal, Vol. 739, Issue 1; Other Information: DOI: 10.1088/0004-637X/739/1/27; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE LOW-MASS INITIAL MASS FUNCTION IN THE 30 DORADUS STARBURST CLUSTER
AGE SPREAD IN W3 MAIN: LARGE BINOCULAR TELESCOPE/LUCI NEAR-INFRARED SPECTROSCOPY OF THE MASSIVE STELLAR CONTENT