DIISC-I: The Discovery of Kinematically Anomalous H i Clouds in M 100 Academic Article uri icon


  • 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 s1 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 s1 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 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 cm2 (3). 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.

published proceedings


altmetric score

  • 0.25

author list (cited authors)

  • Gim, H. B., Borthakur, S., Momjian, E., Padave, M., Jansen, R. A., Nelson, D., ... Tumlinson, J.

citation count

  • 2

complete list of authors

  • Gim, Hansung B||Borthakur, Sanchayeeta||Momjian, Emmanuel||Padave, Mansi||Jansen, Rolf A||Nelson, Dylan||Heckman, Timothy M||Kennicutt Jr., Robert C||Fox, Andrew J||Pineda, Jorge L||Thilker, David||Kauffmann, Guinevere||Tumlinson, Jason

publication date

  • November 2021