Galaxy and mass assembly (GAMA): The merging potential of brightest group galaxies

Banks, K.; Brough, S.; Holwerda, B. W.; Hopkins, A. M.; López-Sánchez, R.; Phillipps, S.; Pimbblet, K. A.; Robotham, A. S.G.

Abstract

Using a volume-limited sample of 550 groups from the Galaxy And Mass Assembly Galaxy Group Catalogue spanning the halo mass range 12.8 < log[Mh M?] < 14.2, we investigate the merging potential of central Brightest Group Galaxies (BGGs). We use spectroscopically confirmed close-companion galaxies as an indication of the potential stellar mass buildup of low-redshift BGGs, z . 0.2. We identify 17 close-companion galaxies with projected separations rp < 30 kpc, relative velocities ?v . 300 km s-1, and stellar mass ratios MBGG/MCC = 4 relative to the BGG. These close-companion galaxies yield a total pair fraction of 0.03 ± 0.01. Overall, we find that BGGs in our sample have the potential to grow in stellar mass due to mergers by 2.2 ± 1.5% Gyr-1. This is lower than the stellar mass growth predicted by current galaxy evolution models.

Citation

Banks, K., Brough, S., Holwerda, B. W., Hopkins, A. M., López-Sánchez, R., Phillipps, S., …Robotham, A. S. (2021). Galaxy and mass assembly (GAMA): The merging potential of brightest group galaxies. The Astrophysical journal, 921(1), 9. https://doi.org/10.3847/1538-4357/ac1c0a

• Journal Article Type: Article
• Acceptance Date: Aug 6, 2021
• Online Publication Date: Oct 29, 2021
• Publication Date: 2021-11
• Deposit Date: Jan 11, 2022
• Publicly Available Date: Oct 30, 2022
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 921
• Issue: 1
• Article Number: 47
• Pages: 9
• DOI: https://doi.org/10.3847/1538-4357/ac1c0a
• Keywords: Galaxy evolution; Galaxy groups; Early-type galaxies
• Public URL: https://hull-repository.worktribe.com/output/3886731