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arXiv · 2109.01243

Discovery of a Highly Collimated Flow from the High-Mass Protostar ISOSS J23053+5953 SMM2

T. M.·Rodríguez·P. Hofner·E. D. Araya·Q. Zhang·H. Linz·S. Kurtz·L. Gómez·C. Carrasco-González·V. Rosero
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Abstract

We present Very Large Array C, X, and Q-band continuum observations, as well as 1.3 mm continuum and CO(2-1) observations with the Submillimeter Array toward the high-mass protostellar candidate ISOSS J23053+5953 SMM2. Compact cm continuum emission was detected near the center of the SMM2 core with a spectral index of 0.24 between 6 and 3.6 cm, and a radio luminosity of 1.3 mJy kpc$^2$. The 1.3 mm thermal dust emission indicates a mass of the SMM2 core of 45.8 Msun. The CO(2-1) observations reveal a large, massive molecular outflow centered on the SMM2 core. This fast outflow ($>$ 50 km/s from the cloud systemic velocity) is highly collimated, with a broader, lower-velocity component. The large values for outflow mass (45.2 Msun), and momentum rate (6 x 10$^{-3}$ Msun km/s/yr) derived from the CO emission are consistent with those of flows driven by high-mass YSOs. The dynamical timescale of the flow is between 1.5 - 7.2 x 10$^4$ yr. We also found from the C18O to thermal dust emission ratio that CO is depleted by a factor of about 20, possibly due to freeze out of CO molecules on dust grains. Our data are consistent with previous findings that ISOSS J23053+5953 SMM2 is an emerging high-mass protostar in an early phase of evolution, with an ionized jet, and a fast, highly collimated, and massive outflow.

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T. M., Rodríguez, P. Hofner, E. D. Araya, Q. Zhang, H. Linz, S. Kurtz, L. Gómez, C. Carrasco-González, V. Rosero. 2021-09-02. Discovery of a Highly Collimated Flow from the High-Mass Protostar ISOSS J23053+5953 SMM2. https://arxiv.org/abs/2109.01243

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