Abstract
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.
Highlights
The buildup of stellar mass in a galaxy is a consequence of the balance among gas supply, removal, and consumption; it is crucial to trace gas flows in and out of galaxies to understand their growth (Sancisi et al 2008; Putman et al 2012)
We report the discovery of two kinematically anomalous atomic hydrogen (HI) 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 HI 21 cm at 3.3 km s−1 spectroscopic and 44 ×30 spatial resolution using the Karl G
We identify regions with young ( 100 Myr) stellar populations in archival far-ultraviolet (FUV) images from the Galaxy Evolution Explorer (GALEX), and regions with current massive star formation ( 10 Myr) in new Hα images acquired at the Vatican Advanced Technology Telescope (VATT)
Summary
Outflows) are expected to exhibit kinematics that are inconsistent with the galaxy’s rotation, showing up as spurs or bridges in the position-velocity (PV) diagram (Sancisi et al 2008, and references therein). AHCs were detected in face-on galaxies such as M 101 (van der Hulst & Sancisi 1988), NGC 628 (Kamphuis & Briggs 1992), and NGC 6946 (Kamphuis & Sancisi 1993; Boomsma et al 2008) by their large velocity offsets from the rotating HI disk of |δv| ≈130–150, ≈100, and >50 km s−1 respectively Each of these studies led to a different conclusion about the origins of the AHCs, e.g., collisions with tidally stripped gas clouds for M 101, disk perturbation due to gas accretion in NGC 628, and star formation feedback in NGC 6946. This study explored the multi-phase outflows including those with cool gas components, while Nelson et al (2020) analyzed the numerous sub-kpc sized individual clouds and found to populate the hot CGM of massive halos in IllustrisTNG50 These studies implied that the properties of AHCs in galaxies will be studied in the context of large-scale cosmological hydrodynamic simulations. We adopt the luminosity distance for M 100 of 13.93±0.12 Mpc, as provided by the Cosmicflows-3 database (Tully et al 2016), giving a linear scale of (14. 80 ± 0.13) kpc−1 2
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
