Kinematics of the Ultra-High-Velocity Gas in the Expanding Molecular Shell Adjacent to the W44 Supernova Remnant
Abstract
High-velocity compact cloud (HVCC) is a peculiar category of molecular clouds detected in the central molecular zone of our Galaxy (Oka et al. 1998, 2007, and 2012). They are characterized by compact appearances (d < 5 pc) and very large velocity widths (Δ V > 50 km s-1). Some of them show high CO J=3-2/J=1-0 intensity ratios (>= 1.5), indicating that they consist of dense and warm molecular gas. Dispite a number of efforts, we have not reached a comprehensive interpretation of HVCCs. Recently, we detected an extraordinaly broad velocity width feature, the `Bullet', in the molecular cloud interacting with the W44 supernova remnant. The Bullet shares essential properties with HVCCs. Because of its proximity, a close inspection of the Bullet must contribute to the understanding of HVCCs.
- Publication:
-
The Multi-Messenger Astrophysics of the Galactic Centre
- Pub Date:
- January 2017
- DOI:
- 10.1017/S1743921316012473
- Bibcode:
- 2017IAUS..322..151Y
- Keywords:
-
- ISM: clouds;
- ISM: molecules;
- (ISM:) supernova remnants;
- ISM: kinematics and dynamics