SDSS-IV MaNGA: The Effect of Stellar Mass and Halo Mass on the Assembly Histories of Satellite Galaxies

Abstract

We combine an unprecedented MaNGA sample of over 3000 passive galaxies in the stellar mass range 109–1012 M ⊙ with the Sloan Digital Sky Survey group catalog by Tinker to quantify how central and satellite formation, quantified by radial profiles in stellar age, [Fe/H], and [Mg/Fe], depends on the stellar mass of the galaxy (M *) and the mass of the host halo (M h ). After controlling for M * and M h , the stacked spectra of centrals and satellites beyond the effective radius (r e ) show small, yet significant differences in multiple spectral features at the 1% level. According to spectral fitting with the code alf, a primary driver of these differences appears to be [Mg/Fe] variations, suggesting that stellar populations in the outskirts of satellites formed more rapidly than the outer populations of centrals. To probe the physical mechanisms that may be responsible for this signal, we examined how satellite stellar populations depend on M h . We find that satellites in high-M h halos show older stellar ages, lower [Fe/H], and higher [Mg/Fe] compared to satellites in low-M h halos, especially for M * = 109.5–1010.5 M ⊙. These signals lend support to environmentally driven processes that quench satellite galaxies, although variations in the merger histories of central and satellite galaxies also emerge as a viable explanation.

A Survey of Lyα Emission around Damped Lyα Absorbers at z ≈ 2 with the Keck Cosmic Web Imager

“…The inflow of H I is counteracted by outflows of metal-enriched gas powered by active galactic nuclei and/or the late stages of stellar evolution, thereby regulating the rate at which galaxies form their stars (e.g., Kereš et al 2005;Tumlinson et al 2017). Furthermore, the removal of H I from galaxies through environment-driven processes (Gunn & Gott 1972;Kawata & Mulchaey 2008;Cortese et al 2021) is often invoked to explain the quenched fractions and assembly histories of satellite galaxies (e.g., Pasquali et al 2010;Wetzel et al 2013;Gallazzi et al 2021;Trussler et al 2021;Werle et al 2022;Oyarzún et al 2023).…”