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Title: 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 H α 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 × 10 13 cm −2 (3 σ ). 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.  more » « less
Award ID(s):
2009409
NSF-PAR ID:
10327696
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
922
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
69
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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