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arXiv · 1607.01267

Star forming activity in the H II regions associated with IRAS 17160-3707 complex

G. Nandakumar·V. S. Veena·S. Vig·A. Tej·S. K. Ghosh·D. K. Ojha
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Abstract

We present a multiwavelength investigation of star formation activity towards the southern H II regions associated with IRAS 17160-3707, located at a distance of 6.2 kpc with a bolometric luminosity of 830000 Lsun.The ionised gas distribution and dust clumps in the parental molecular cloud are examined in detail using measurements at infrared, submillimeter and radio wavelengths.The radio continuum images at 1280 and 610 MHz obtained using Giant Metrewave Radio Telescope reveal the presence of multiple compact sources as well as nebulous emission.At submillimeter wavelengths, we identify seven dust clumps and estimate their physical properties like temperature: 24 - 30 K, mass: 300 - 4800 Msun and luminosity: 900 - 31700 Lsun using modified blackbody fits to the spectral energy distributions between 70 and 870 um.We find 24 young stellar objects in the mid-infrared, with few of them coincident with the compact radio sources.The spectral energy distributions of young stellar objects have been fitted by the Robitaille models and the results indicate that those having radio compact sources as counterparts host massive objects in early evolutionary stages with best fit age <= 0.2 Myr.We compare the relative evolutionary stages of clumps using various signposts such as masers, ionised gas, presence of young stellar objects and infrared nebulosity and find six massive star forming clumps and one quiescent clump.Of the former, five are in a relatively advanced stage and one in an earlier stage.

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G. Nandakumar, V. S. Veena, S. Vig, A. Tej, S. K. Ghosh, D. K. Ojha. 2016-07-05. Star forming activity in the H II regions associated with IRAS 17160-3707 complex. https://doi.org/10.3847/0004-6256%2F152%2F5%2F146

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