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arXiv · 1906.08848

A new, rotating hot corino in Serpens

R. Martin-Domenech·K. I. Oberg·J. B. Bergner·J. K. Jorgensen
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Abstract

We have observed 29 transitions corresponding to 12 distinct species and 7 additional isotopologs toward the deeply embedded Class 0 young stellar object Ser-emb 1 with the Atacama Large Millimeter Array at 1 mm. The detected species include CH3OH and two complex organic molecules, CH3OCH3 and CH3OCHO. The emission of CH3OH and the two COMs is compact, and the CH3OH rotational temperature is 261 (46) K, implying that Ser-emb 1 hosts a hot corino. The derived CH3OH, CH3OCH3 and CH3OCHO column densities are at least 1.2 (0.4)E17 cm-2, 9.2 (3.8)E16 cm-2, and 9.1 (3.6)E16 cm-2, respectively, comparable to the values found for other Class 0 hot corinos. In addition, we observe evidence of rotation at compact scales: two of the more strongly detected lines, corresponding to C18O and H2CO present spatially resolved red- and blue-shifted compact emission orthogonal to the direction of a jet and outflow traced by CO, SiO, and several other molecules. The spatial coincidence of the hot corino emission and a possible disk in a compact region around the central protostar suggests that these structures may be physically and/or chemically related.

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R. Martin-Domenech, K. I. Oberg, J. B. Bergner, J. K. Jorgensen. 2019-06-20. A new, rotating hot corino in Serpens. https://doi.org/10.3847/1538-4357%2Fab2a08

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