TY - JOUR
T1 - Discovery of a large-scale H i plume in the NGC 7194 group
AU - Pak, Mina
AU - Baek, Junhyun
AU - Lee, Joon Hyeop
AU - Chung, Aeree
AU - Owers, Matt
AU - Jeong, Hyunjin
AU - Sung, Eon-Chang
AU - Sheen, Yun-Kyeong
N1 - © 2024. The Author(s). Published by the American Astronomical Society. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
PY - 2024/1/1
Y1 - 2024/1/1
N2 - We present the discovery of a new H i structure in the NGC 7194 group from the observations using the Karl G. Jansky Very Large Array. NGC 7194 group is a nearby (z ∼ 0.027) small galaxy group with five quiescent members. The observations reveal a 200 kpc long H i plume that spans the entire group with a total mass of MH I = 3.4 × 1010 M⊙. The line-of-sight velocity of the H i gas gradually increases from south (7200 km s−1) to north (8200 km s−1), and the local velocity dispersion is up to 70 km s−1. The structure is not spatially coincident with any member galaxies but it shows close associations with a number of blue star-forming knots. Intragroup H i gas is not rare, but this particular structure is still one of the unusual cases in the sense that it does not show any clear connection with sizable galaxies in the group. We discuss the potential origins of this large-scale H i gas in the NGC 7194 group and its relation with the intergalactic star-forming knots. We propose that this H i feature could have originated from tidal interactions among group members or the infall of a late-type galaxy into the group. Alternatively, it might be leftover gas from flyby intruders.
AB - We present the discovery of a new H i structure in the NGC 7194 group from the observations using the Karl G. Jansky Very Large Array. NGC 7194 group is a nearby (z ∼ 0.027) small galaxy group with five quiescent members. The observations reveal a 200 kpc long H i plume that spans the entire group with a total mass of MH I = 3.4 × 1010 M⊙. The line-of-sight velocity of the H i gas gradually increases from south (7200 km s−1) to north (8200 km s−1), and the local velocity dispersion is up to 70 km s−1. The structure is not spatially coincident with any member galaxies but it shows close associations with a number of blue star-forming knots. Intragroup H i gas is not rare, but this particular structure is still one of the unusual cases in the sense that it does not show any clear connection with sizable galaxies in the group. We discuss the potential origins of this large-scale H i gas in the NGC 7194 group and its relation with the intergalactic star-forming knots. We propose that this H i feature could have originated from tidal interactions among group members or the infall of a late-type galaxy into the group. Alternatively, it might be leftover gas from flyby intruders.
UR - http://www.scopus.com/inward/record.url?scp=85182578097&partnerID=8YFLogxK
UR - https://purl.org/au-research/grants/arc/CE170100013
U2 - 10.3847/2041-8213/ad0ed2
DO - 10.3847/2041-8213/ad0ed2
M3 - Article
AN - SCOPUS:85182578097
SN - 2041-8205
VL - 961
SP - 1
EP - 6
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 1
M1 - L11
ER -