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

We revisit the color bimodality of galaxies using the extensive EFIGImorphological classification of nearby galaxies. The galaxy SDSS images in theg, r and i bands are decomposed as bulge+disk using SourceXtractor++. Thespectral energy distributions made of our gri photometry complemented withGALEX NUV are fitted with ZPEG in order to estimate the stellar masses andspecific star formations rates (sSFR) of whole galaxies as well as their bulgeand disk components. The absolute NUV-r color versus stellar mass diagram showsa continuous relationship between the present sSFR of galaxies and theirstellar mass, that spans all morphological types of the Hubble sequence.Irregular galaxies to Sab spirals make up the Blue Cloud, the Green Plain(formerly Valley) is made up of early-type spirals (S0a-Sa) while the RedSequence contains all lenticular and elliptical galaxies, with systematicallyhigher masses for the ellipticals. Galaxies across the Green Plain undergo amarked growth by a factor 2 to 3 in their bulge-to-total mass ratio and asystematic profile change from pseudo to classical bulges, as well as asignificant reddening interpreted as star formation fading in their disks.Therefore, the Green Plain is a transition region, and we exclude apredominantly quick transit due to rapid quenching. We suggest that tracers ofincreased star formation (bright HII regions, spiral arms, flocculence)determine the limited scatter of the Main Sequence of star-forming galaxies.The high frequency of bars for all spirals as well as the stronger spiral armsand flocculence in the knee of the Green Plain suggest that internal dynamics,likely triggered by flybys or mergers, may be the key to the bulge growth ofmassive disk galaxies, marker of the aging of galaxies from star forming toquiescence. The Hubble sequence can then be considered as an inverse sequenceof galaxy physical evolution.

Aging of galaxies along the morphological sequence, marked by bulge growth and disk quenching