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تسجيل مستخدم جديدSK 1: A Possible Case of Triggered Star Formation in Perseus
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According to a triggered star formation scenario (e.g. Martin-Pintado & Cernicharo 1987) outflows powered by young stellar objects shape the molecular clouds, can dig cavities, and trigger new star formation. NGC 1333 is an active site of low- and intermediate star formation in Perseus and is a suggested site of self-regulated star formation Norman & Silk 1980. Therefore it is a suitable target for a study of triggered star formation (e.g. Sandell & Knee 2001, SK 1). On the other hand, continuum sub-mm observations of star forming regions can detect dust thermal emission of embedded sources (which drive outflows), and further detailed structures. Within the framework of our wide-field mapping of star formation regions in the Perseus and Orion molecular clouds using SCUBA at 850 and 450 micrometers, we map NCG 1333 with an area of around 14 x 21. The maps show more structure than the previous maps of the region observed in sub-mm. We have unveiled the known embedded SK 1 source (in the dust shell of the SSV 13 ridge) and detailed structure of the region, among some other young protostars. In agreement with the SK 1 observations, our map of the region shows lumpy filaments and shells/cavities that seem to be created by outflows. The measured mass of SK 1 (~0.07 Msun) is much less than its virial mass (~0.2-1 Msun). Our observations support the idea of SK 1 as an event triggered by outflow-driven shells in NGC 1333 (induced by an increase in gas pressure and density due to radiation pressure from the stellar winds, that have presumably created the dust shell). This kind of evidences provides a more thorough understanding of the star formation regulation processes.
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