Speaker
Description
The formation of high-mass stars remains one of the key open questions in astrophysics. While structures familiar from low-mass star formation such as outflows, jets, and rotating centroids have been observed in massive star-forming regions, detailed studies at spatial scales of a few hundred AU are still rare and limited to only a handful of sources.
Recent ALMA observations of the high-mass protostellar object G23.6 have revealed a remarkable ring-shaped circumstellar disk with an inner cavity, the first of its kind to be resolved with this morphology at such small scales. Proper motion measurements of methanol masers trace the ring's expansion away from the central source. Strikingly, the ring is rich in complex organic molecules, while its centre appears depleted of molecular gas and dust, except for localized emission from sulfur-bearing species. These may trace shocks at the disk-envelope interface, potentially driven by infall or outflows. A mild velocity gradient across the ring in multiple molecular lines is consistent with a slow component of rotation.
In this presentation, I will explore the unique morphology and kinematics of this circumstellar ring, present detailed analyses of its molecular content, and discuss its implications for models of massive star formation.
| Category | Disk substructures and implications |
|---|---|
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