DIISC-I: The Discovery of Kinematically Anomalous H I Clouds in M 100
Abstract
We report the discovery of two kinematically anomalous atomic hydrogen (H I) clouds in M 100 (NGC 4321), which was observed as part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium (DIISC) survey in H I 21 cm at 3.3 km s-1 spectroscopic and 44″ × 30″ spatial resolution using the Karl G. Jansky Very Large Array. 15 15 The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. These clouds were identified as structures that show significant kinematic offsets from the rotating disk of M 100. The velocity offsets of 40 km s-1 observed in these clouds are comparable to the offsets seen in intermediate-velocity clouds (IVCs) in the circumgalactic medium (CGM) of the Milky Way and nearby galaxies. We find that one anomalous cloud in M 100 is associated with star-forming regions detected in Hα and far-ultraviolet imaging. Our investigation shows that anomalous clouds in M 100 may originate from multiple mechanisms, such as star formation feedback-driven outflows, ram pressure stripping, and tidal interactions with satellite galaxies. Moreover, we do not detect any cool CGM at 38.8 kpc from the center of M 100, giving an upper limit of N(H I) ≤1.7 × 1013 cm-2 (3σ). Since M 100 is in the Virgo cluster, the nonexistence of neutral/cool CGM is a likely pathway for turning it into a red galaxy.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 2021
- DOI:
- 10.3847/1538-4357/ac2303
- arXiv:
- arXiv:2109.06247
- Bibcode:
- 2021ApJ...922...69G
- Keywords:
-
- 834;
- 847;
- 1772;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 19 pages, 3 tables, 7 figures, Accepted for publication at ApJ