MaNGA 8313-1901: Gas Accretion Observed in a Blue Compact Dwarf Galaxy?

Journal Article · Mon Oct 17 00:00:00 EDT 2022 · The Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/ac9056· OSTI ID:2425218

Ju, Mengting ^[1]; Yin, Jun ^[2]; Liu, Rongrong ^[1]; Hao, Lei ^[3]; Shao, Zhengyi ^[2]; Feng, Shuai ^[4]; Riffel, Rogério ^[5]; Liu, Chenxu ^[6]; Stark, David V. ^[7]; Shen, Shiyin ^[2]; Telles, Eduardo ^[8]; Fernández-Trincado, José G. ^[9]; Wang, Junfeng ^[10]; Xu, Haiguang ^[11]; Bizyaev, Dmitry ^[12]; Rong, Yu ^[13]

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1. Chinese Academy of Sciences, Shanghai (China); University of Chinese Academy of Sciences, Beijing (China)
2. Chinese Academy of Sciences, Shanghai (China); Key Lab for Astrophysics, Shanghai (China)
3. Chinese Academy of Sciences, Shanghai (China)
4. Hebei Normal University, Shijiazhuang (China); Hebei Key Laboratory of Photophysics Research and Application, Shijiazhuang (China)
5. Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Laboratório Interinstitucional de e-Astronomia—LIneA, Rio de Janeiro, RJ (Brazil)
6. University of Texas at Austin, TX (United States)
7. Haverford College, PA (United States); University of Washington, Seattle, WA (United States)
8. Observatório Nacional R. Gen. José Cristino, Janeiro (Brazil)
9. Universidad Católica del Norte, Antofagasta (Chile)
10. Xiamen University, Fujian (China)
11. Shanghai Jiao Tong University (China)
12. Apache Point Observatory and New Mexico State University, Sunspot, NM (United States); Moscow State University (Russia)
13. University of Science and Technology of China, Anhui (China)

Gas accretion is an important process in the evolution of galaxies, but it has limited direct observational evidences. In this paper, we report the detection of a possible ongoing gas accretion event in a blue compact dwarf (BCD) galaxy, MaNGA 8313-1901, observed by the Mapping Nearby Galaxies and Apache Point Observatory (MaNGA) program. This galaxy has a distinct off-centered blue clump to the northeast (the NE clump) that shows low metallicity and enhanced star formation. The kinematics of the gas in the NE clump also seems to be detached from the host BCD galaxy. Together with the metallicity drop of the NE clump, it suggests that the NE clump likely has an external origin, such as gas accretion or galaxy interaction, rather than an internal origin, such as an H II complex in the disk. After removing the underlying host component, we find that the spectrum of the "pure" clump can match very well with a modeled spectrum containing a stellar population of the young stars (≤7 Myr) only. This may imply that the galaxy is experiencing an accretion of cold gas, instead of a merger event involving galaxies with significant preexisting old stars. We also find signs of another clump (the SW clump) at the southwest corner of the host galaxy, and the two clumps may share the same origin of gas accretion.

• Research Organization: US Department of Energy (USDOE), Washington, DC (United States). Office of Science, Sloan Digital Sky Survey (SDSS)
• Sponsoring Organization: USDOE
• OSTI ID: 2425218
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 938; ISSN 0004-637X
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
Astronomy & Astrophysics
Dwarf galaxies
Galaxy abundances
Galaxy kinematics
Star formation