A photometric and spectroscopic investigation of star formation in the very young open cluster NGC 6383
Abstract
Context. The very young open cluster NGC 6383 centered on the O-star binary HD 159176 is an interesting place for studying the impact of early-type stars with strong radiation fields and powerful winds on the formation processes of low-mass stars.
Aims: To investigate this process, it is necessary to determine the characteristics (age, presence, or absence of circumstellar material) of the population of low-mass pre-main-sequence (PMS) stars in the cluster.
Methods: We obtained deep UBV(RI)c Hα photometric data of the entire cluster as well as medium-resolution optical spectroscopy of a subsample of X-ray selected objects.
Results: Our spectroscopic data reveal only very weak Hα emission lines in a few X-ray selected PMS candidates. We photometrically identify a number of Hα emission candidates but their cluster membership is uncertain. We find that the fainter objects in the field of view have a wide range of extinction (up to AV = 20), one X-ray selected OB star having AV ≃ 8.
Conclusions: Our investigation uncovers a population of PMS stars in NGC 6383 that are probably coeval with HD 159176. In addition, we detect a population of reddened objects that are probably located at different depths within the natal molecular cloud of the cluster. Finally, we identify a rather complex spatial distribution of Hα emitters, which is probably indicative of a severe contamination by foreground and background stars.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- February 2010
- DOI:
- 10.1051/0004-6361/200912780
- arXiv:
- arXiv:1001.0696
- Bibcode:
- 2010A&A...511A..25R
- Keywords:
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- stars: pre-main sequence;
- X-rays: stars;
- open clusters and associations: individual: NGC 6383;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted for publication in Astronomy &