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The Dense Molecular Cores in the IRAS 21391+5802 region

Maria T. Beltran·Josep M. Girart·Robert Estalella·Paul T. P. Ho
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Abstract

We present a detailed kinematical study and modeling of the emission of the molecular cores at ambient velocities surrounding IRAS 21391+5802, an intermediate-mass protostar embedded in IC 1396N. The high-density gas emission is found in association with three dense cores associated with the YSOs BIMA 1, BIMA 2, and BIMA 3. The CS (5-4) and CH3OH (5-4) emission around BIMA 1 has been modeled by considering a spatially infinitely thin ring seen edge-on by the observer. From the model we find that CS is detected over a wider radii range than CH3OH. A bipolar outflow is detected in the CS (2-1) line centered near BIMA 1. This outflow could be powered by a yet undetected YSO, BIMA 1W, or alternatively could be part of the BIMA 1 molecular outflow. The CS and CH3OH emission associated with the intermediate-mass protostar BIMA 2 is highly perturbed by the bipolar outflow even at cloud velocities, confirming that the protostar is in a very active stage of mass loss. For YSO BIMA 3 the lack of outflow and of clear evidence of infall suggests that both outflow and infall are weaker than in BIMA 1, and that BIMA 3 is probably a more evolved object.

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Maria T. Beltran, Josep M. Girart, Robert Estalella, Paul T. P. Ho. 2004-07-06. The Dense Molecular Cores in the IRAS 21391+5802 region. https://doi.org/10.1051/0004-6361%3A20041163

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