English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The colors and chemical abundances of early-type galaxies at redshifts z<0.3are studied using a sample of nearly 9000 galaxies, selected from the SloanDigital Sky Survey using morphological and spectral criteria. In this sample,redder galaxies have larger velocity dispersions. Color also correlates withmagnitude and size, but these correlations are entirely due to the L-sigma andR_o-sigma relations: the primary correlation is color-sigma. The red light inearly-type galaxies is, on average, slightly more centrally concentrated thanthe blue. Because of these color gradients, the strength of thecolor--magnitude relation depends on whether or not the colors are definedusing a fixed metric aperture. Chemical evolution and star formation historiesof early-type galaxies are investigated using co-added spectra of similarobjects. At fixed sigma, the population at z ~ 0.2 had weaker Mg_2 and strongerH_beta absorption compared to the population at z ~ 0. It was also bluer.Comparison of these colors and line-strengths, and their evolution, withsingle-burst stellar population models suggests a formation time of 9 Gyrs ago,consistent with a Fundamental Plane analysis of this sample.

Early-Type Galaxies in the Sloan Digital Sky Survey. IV. Colors and Chemical Evolution