Bibcode
Puga, E.; Hony, S.; Neiner, C.; Lenorzer, A.; Hubert, A.-M.; Waters, L. B. F. M.; Cusano, F.; Ripepi, V.
Bibliographical reference
Astronomy and Astrophysics, Volume 503, Issue 1, 2009, pp.107-119
Advertised on:
8
2009
Journal
Citations
28
Refereed citations
22
Description
Aims: Using Spitzer/IRAC observations of a region to be observed by the
CoRoT satellite, we have unraveled a new complex star-forming region at
low metallicity in the outer Galaxy. We perform a study of S284 in order
to outline the chain of events in this star-forming region. Methods: We used four-band Spitzer/IRAC photometry as well as Hα
imaging obtained with INT/WFC. Combining these data with the optical
photometry obtained in the frame of CoRoTs preparation and the 2MASS
catalog we analysed the properties and distribution of young stellar
objects (YSOs) associated with point-like sources. We also studied the
SEDs of regions of extended emission, complementing our dataset with
IRAS and MSX data. Results: We find that S284 is unique in several
ways: it is very isolated at the end of a spiral arm and both the
diffuse dust and ionized emission are remarkably symmetric. We have
partially resolved the central clusters of the three bubbles present in
this region. Despite the different scales observed in its
multiple-bubble morphology, our study points to a very narrow spread of
ages among the powering high-mass clusters. In contrast, the particular
sawtooth structure of the extended emission at the rim of each ionized
bubble harbours either small lower-mass clusters with a younger stellar
population or individual young reddened protostars. In particular,
triggered star formation is considered to be at work in these regions.
Based on data obtained with IRAC onboard Spitzer (Program ID 3340) and
the WFC at Isaac Newton Telescope at La Palma.
Tables 3 and 4 are only available in electronic form at
http://www.aanda.org