TY - JOUR
T1 - SDSS-IV MaNGA
T2 - Cannibalism Caught in the Act - On the Frequency of Occurrence of Multiple Cores in Brightest Cluster Galaxies
AU - Hsu, Yun Hsin
AU - Lin, Yen Ting
AU - Huang, Song
AU - Nelson, Dylan
AU - Rodriguez-Gomez, Vicente
AU - Lai, Hsuan Ting
AU - Greene, Jenny
AU - Leauthaud, Alexie
AU - Aragón-Salamanca, Alfonso
AU - Bundy, Kevin
AU - Emsellem, Eric
AU - Merrifield, Michael
AU - More, Surhud
AU - Okabe, Nobuhiro
AU - Rong, Yu
AU - Brownstein, Joel R.
AU - Lane, Richard R.
AU - Pan, Kaike
AU - Schneider, Donald P.
N1 - Funding Information:
We thank Gabriel Torrealba for developing the Ellipse package used in this work. We are grateful to Wei-Hao Wang, Kyle Westfall, James Lottes, Andrew Cooper, David Wake, Michael Blanton, Xiaohu Yang, and Ting-Wen Lan for helpful comments, and Taira Oogi and Abdurro’uf for help with handling of simulated and MaNGA data, respectively. We thank an anonymous referee whose comments have improved the clarity of the paper. Y.H.H. and Y.T.L. are grateful for support from the Ministry of Science and Technology of Taiwan under grants MOST 110-2112-M-001-004 and MOST 109-2112-M-001-005, and a Career Development Award from Academia Sinica (AS-CDA-106-M01). D.N. acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG) through an Emmy Noether Research Group (grant No. NE 2441/1-1). Y.T.L. thanks I.H., L.Y.L. and A.L.L. for constant encouragement and inspiration.
Funding Information:
Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS acknowledges support and resources from the Center for High-performance Computing at the University of Utah. The SDSS website is www.sdss.org .
Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/7/1
Y1 - 2022/7/1
N2 - Although it is generally accepted that massive galaxies form in a two-phased fashion, beginning with a rapid mass buildup through intense starburst activities followed by primarily dry mergers that mainly deposit stellar mass at outskirts, the late time stellar mass growth of brightest cluster galaxies (BCGs), the most massive galaxies in the universe, is still not well understood. Several independent measurements have indicated a slower mass growth rate than predictions from theoretical models. We attempt to resolve the discrepancy by measuring the frequency of BCGs with multiple cores, which serve as a proxy of the merger rates in the central region and facilitate a more direct comparison with theoretical predictions. Using 79 BCGs at z = 0.06-0.15 with integral field spectroscopic data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, we obtain a multiple-core fraction of 0.11 ± 0.04 at z ≈ 0.1 within an 18 kpc radius from the center, which is comparable to the value of 0.08 ± 0.04 derived from mock observations of 218 simulated BCGs from the cosmological hydrodynamical simulation IllustrisTNG. We find that most cores that appear close to the BCGs from imaging data turn out to be physically associated systems. Anchoring on the similarity in the multiple-core frequency between the MaNGA and IllustrisTNG, we discuss the mass growth rate of BCGs over the past 4.5 Gyr.
AB - Although it is generally accepted that massive galaxies form in a two-phased fashion, beginning with a rapid mass buildup through intense starburst activities followed by primarily dry mergers that mainly deposit stellar mass at outskirts, the late time stellar mass growth of brightest cluster galaxies (BCGs), the most massive galaxies in the universe, is still not well understood. Several independent measurements have indicated a slower mass growth rate than predictions from theoretical models. We attempt to resolve the discrepancy by measuring the frequency of BCGs with multiple cores, which serve as a proxy of the merger rates in the central region and facilitate a more direct comparison with theoretical predictions. Using 79 BCGs at z = 0.06-0.15 with integral field spectroscopic data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, we obtain a multiple-core fraction of 0.11 ± 0.04 at z ≈ 0.1 within an 18 kpc radius from the center, which is comparable to the value of 0.08 ± 0.04 derived from mock observations of 218 simulated BCGs from the cosmological hydrodynamical simulation IllustrisTNG. We find that most cores that appear close to the BCGs from imaging data turn out to be physically associated systems. Anchoring on the similarity in the multiple-core frequency between the MaNGA and IllustrisTNG, we discuss the mass growth rate of BCGs over the past 4.5 Gyr.
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U2 - 10.3847/1538-4357/ac6d66
DO - 10.3847/1538-4357/ac6d66
M3 - Article
AN - SCOPUS:85134547212
SN - 0004-637X
VL - 933
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
M1 - 61
ER -