Subarcsecond Imaging of the High-Mass Star Forming Region Onsala 1
arXiv:0904.3161 · doi:10.1088/0004-637X/698/2/1981
Abstract
We report subarcsecond images of the high-mass star forming region Onsala 1 (ON 1) made with the Submillimeter Array (SMA) at 0.85 mm and the Very Large Array at 1.3 cm and 3.6 cm. ON~1 is one of the smallest ultracompact HII regions in the Galaxy and exhibits various star formation signposts. With our VLA and SMA observations, two new cm-wave sources and five sub-mm dust sources, respectively, within a field of ~3" (corresponding to a linear scale of 0.05 pc) are identified, indicating the multiplicity at the center of the ON 1 region. The dust and gas masses of these sub-mm sources are in the range of 0.8 to 6.4 M_sun. Among the five sub-mm dust sources, SMA2, with a dust and gas mass of 2.6 M_sun, demonstrates several star formation signatures, and hence likely represents an intermediate-mass (or even high-mass) star forming core. Due to the low star formation efficiency of ~10%, we suggest that star formation in the ON 1 region will continue. For example, SMA4 and SMA5 are not associated with any star formation signatures and likely mark star formation cores at very early evolutionary stages.
accepted for publication in ApJ
References in corpus (7)
- Toward Understanding Massive Star Formation
- A magnetically collimated jet from an evolved star
- H2O Maser Observations of Candidate Post-AGB Stars and Discovery of Three High-velocity Water Sources
- The spatio-kinematical structure and distance of the pre-planetary nebula IRAS 19134+2131
- Proper Motions of OH Masers and Magnetic Fields in Massive Star-Forming Regions
- VLBI Observations of Water Masers in Onsala 1: Massive Binary Star Forming Site?
- EVLA Observations of OH Masers in ON 1
Cited by in corpus (6)
- Trigonometric Parallaxes of 6.7 GHz Methanol Masers
- Deuteration as an evolutionary tracer in massive-star formation
- Early stages of cluster formation: fragmentation of massive dense cores down to ~1000 AU
- Properties of dense cores in clustered massive star-forming regions at high angular resolution
- DNC/HNC and N2D+/N2H+ ratios in high-mass star forming cores
- SMA observations of C2H in High-Mass Star Forming Regions