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arXiv · astro-ph/0305135

NGC7538S - a High-Mass Protostar with a Massive Rotating Disk

G. Sandell·M. Wright·J. R. Forster
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Abstract

We report the detection of a massive rotating disk around the high-mass Class 0 candidate NGC 7538S. The disk is well-resolved with BIMA (HPBW =3.7") in 3.4 mm continuum and in H13CN J = 1 - 0. It is seen nearly edge on and has a size of ~ 30,000 AU. A young, powerful outflow perpendicular to the rotating disk is mapped in SiO J = 2 - 1 and HCO+ J = 1 - 0. The dynamical age of the outflow is < 10,000 yr. The velocity gradient seen in H13CN is consistent with Keplerian rotation. Assuming that the gas is gravitationally bound, the mass of the central object is ~ 40 Msun. The mass of the continuum ``disk'' is <= 100 Msun and has a luminosity of 10^4 Lsun. H13CN gives a mass ~ 400 Msun for the rotating disk, and ~ 1000 Msun for the extended (20") envelope. Our observations confirm that this is an extremely massive protostar in its earliest stages.

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G. Sandell, M. Wright, J. R. Forster. 2003-05-08. NGC7538S - a High-Mass Protostar with a Massive Rotating Disk. https://doi.org/10.1086/376612

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