Pre-Orion Cores in the Trifid Nebula
نویسنده
چکیده
The Trifid nebula is a young HII region undergoing a burst of star formation. In this article, we report on far-infrared and millimeter continuum and line observations of several massive and bright protostellar sources in the vicinity of the exciting star of the nebula, just behind the ionization front. These objects are probably young protostars (Class 0) and are associated with very massive cores (M ∼ 8− 90M⊙) powering young energetic outflows. Analysis of the far-infrared emission in the 45− 200 μm range from ISO/LWS data shows that they are embedded in cold dense material. Inspection of their physical properties suggest that they are similar to the dust protostellar cores observed in Orion, although at an earlier evolutionary “Pre-Orion” stage. The cores are embedded in a compressed layer of dense gas. Based on comparison with the models, we find that the cores could have formed from the fragmentation of the layer and that the birth of the protostars was triggered by the expansion of the Trifid nebula. Subject headings: ISM: individual (Trifid); ISM: jets and outflows; ISM: molecules stars: formation
منابع مشابه
Star formation in the Trifid Nebula Cores and filaments
Aims. We aim to characterize the properties of the prestellar and protostellar condensations to understand the star formation processes at work in a young HII region Methods. We have obtained maps of the 1.25mm thermal dust emission and the molecular gas emission over a region of 20 ′ × 10 ′ around the Trifid Nebula (M20), with the IRAM 30m and the CSO telescopes as well as in the mid-infrared ...
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