SDSS-IV MaNGA: How the Stellar Populations of Passive Central Galaxies Depend on Stellar and Halo Mass

• Published in: The Astrophysical journal Vol. 933; no. 1; pp. 88 - 108
• Main Authors: Oyarzún, Grecco A., Bundy, Kevin, Westfall, Kyle B., Tinker, Jeremy L., Belfiore, Francesco, Argudo-Fernández, Maria, Zheng, Zheng, Conroy, Charlie, Masters, Karen L., Wake, David, Law, David R., McDermid, Richard M., Aragón-Salamanca, Alfonso, Parikh, Taniya, Yan, Renbin, Bershady, Matthew, Sánchez, Sebastián F., Andrews, Brett H., Fernández-Trincado, José G., Lane, Richard R., Bizyaev, D., Boardman, Nicholas Fraser, Lacerna, Ivan, Brownstein, J. R., Drory, Niv, Zhang, Kai
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 01.07.2022; IOP Publishing
• Subjects: Assembly; ASTRONOMY AND ASTROPHYSICS; Astrophysics; Early-type galaxies; Elliptical galaxies; Galactic halos; Galaxies; Galaxy abundances; Galaxy ages; Galaxy dark matter halos; Galaxy environments; Galaxy evolution; Galaxy properties; Galaxy spectroscopy; Galaxy stellar content; Halos; Iron; Magnesium; Quenched galaxies; Signal to noise ratio; Stars & galaxies; Stellar mass; Stellar populations; Systematic errors
• ISSN: 0004-637X; 1538-4357
• DOI: 10.3847/1538-4357/ac7048

Abstract We analyze spatially resolved and co-added SDSS-IV MaNGA spectra with signal-to-noise ratio ∼100 from 2200 passive central galaxies ( z ∼ 0.05) to understand how central galaxy assembly depends on stellar mass ( M * ) and halo mass ( M h ). We control for systematic errors in M h by employing a new group catalog from Tinker and the widely used Yang et al. catalog. At fixed M * , the strengths of several stellar absorption features vary systematically with M h . Completely model-free, this is one of the first indications that the stellar populations of centrals with identical M * are affected by the properties of their host halos. To interpret these variations, we applied full spectral fitting with the code alf . At fixed M * , centrals in more massive halos are older, show lower [Fe/H], and have higher [Mg/Fe] with 3.5 σ confidence. We conclude that halos not only dictate how much M * galaxies assemble but also modulate their chemical enrichment histories. Turning to our analysis at fixed M h , high- M * centrals are older, show lower [Fe/H], and have higher [Mg/Fe] for M h > 10 12 h −1 M ⊙ with confidence >4 σ . While massive passive galaxies are thought to form early and rapidly, our results are among the first to distinguish these trends at fixed M h . They suggest that high- M * centrals experienced unique early formation histories, either through enhanced collapse and gas fueling or because their halos were early forming and highly concentrated, a possible signal of galaxy assembly bias.