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arXiv · 1507.02695

Kinematic Detection of the Galactic Nuclear Disc

Ralph Schönrich·Michael Aumer·Stuart E. Sale
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Abstract

We report the detection of the Galactic nuclear disc in line-of-sight kinematics of stars, measured with infrared spectroscopy from APOGEE. This stellar component of the nuclear disc has an extent and rotation velocity V ~ 120kms comparable to the gas disc in the central molecular zone. The current data suggest that this disc is kinematically cool and has a small vertical extent of order 50pc. The stellar kinematics suggest a truncation radius/steep decline of the stellar disc at a galactocentric radius R ~ 150pc, and provide tentative evidence for an overdensity at the position of the ring found in the molecular gas disc.

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Ralph Schönrich, Michael Aumer, Stuart E. Sale. 2015-10-05. Kinematic Detection of the Galactic Nuclear Disc. https://doi.org/10.1088/2041-8205%2F812%2F2%2Fl21

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