Kinematics of a Hot Massive Accretion Disk Candidate

Characterizing rotation, infall, and accretion disks around high-mass protostars is an important topic in massive star formation research. With the Australia Telescope Compact Array and the Very Large Array, we studied a massive disk candidate at high angular resolution in ammonia [NH3(4, 4) and (5,...

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Bibliographic Details
Main Authors: Beuther, H., Walsh, Andrew
Format: Journal Article
Published: Institute of Physics Publishing 2008
Subjects:
Online Access:http://hdl.handle.net/20.500.11937/18769
Description
Summary:Characterizing rotation, infall, and accretion disks around high-mass protostars is an important topic in massive star formation research. With the Australia Telescope Compact Array and the Very Large Array, we studied a massive disk candidate at high angular resolution in ammonia [NH3(4, 4) and (5, 5)] tracing the warm disk but not the envelope. The observations resolved at ~0.4" resolution (corresponding to ~1400 AU) a velocity gradient indicative of rotation perpendicular to the molecular outflow. Assuming a Keplerian accretion disk, the estimated protostar-disk mass would be high, similar to the protostellar mass. Furthermore, the position-velocity diagram exhibits additional deviation from a Keplerian rotation profile that may be caused by infalling gas and/or a self-gravitating disk. Moreover, a large fraction of the rotating gas is at temperatures &gt;100 K, markedly different from typical low-mass accretion disks. In addition, we resolve a central double-lobe centimeter continuum structure perpendicular to the rotation. We identify this with an ionized, optically thick jet. Resorting Query Results <a href="http://adsabs.harvard.edu/cgi-bin/nph-abs_connect">http://adsabs.harvard.edu/cgi-bin/nph-abs_connect</a> 73