The differences between mass- and light-derived structural parameters over time for MaNGA elliptical galaxies
Date Issued
2022
Author(s)
Ibarra-Medel H.
Avila-Reese V.
Lacerna I.
Rodríguez-Puebla A.
Vázquez-Mata J.A.
Hernández-Toledo H.M.
Sánchez S.F.
DOI
http://dx.doi.org/10.1093/mnras/stab3765
Abstract
We apply stellar population synthesis analysis to obtain spatially resolved archaeological inferences for a large sample of 'red and dead' Elliptical galaxies (Classical Ellipticals, CLEs) from the MaNGA/SDSS-IV DR15 surv e y. From their 2D stellar light and mass maps, we explore the differences between the radial mass and light distributions in the rest-frame bands g , r , and i as functions of look-back time, t lb , or redshift, z. We characterize these differences through the ratios between the following mass- and light-derived global properties: Sizes, concentrations, and effective surface densities. We find that the mass-to-light ratios of these properties change with t lb , more the more massive the galaxies are. The CLE galaxy archaeological progenitors are, on average, less compact, concentrated, and dense in light than in mass as z decreases. Ho we ver, at later times, when also the evolution of the progenitors becomes passive at all radii, there is an upturn in these trends and the differences between mass and light in compactness/concentration decrease towards z ∼0. The trends in the ratios of mass-to-light sizes agree qualitatively with results from direct observations in galaxy surv e ys at different redshifts. We discuss the caveats and interpretations of our results, and speculate that the strong structural evolution found in some previous studies for early-type galaxies could be explained partially by photometric changes rather than by intrinsic structural changes. © 2022 Oxford University Press. All rights reserved.


