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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present an analysis of the data produced by the MaNGA prototype run(P-MaNGA), aiming to test how the radial gradients in recent star formationhistories, as indicated by the 4000AA-break (D4000), Hdelta absorption(EW(Hd_A)) and Halpha emission (EW(Ha)) indices, can be useful forunderstanding disk growth and star formation cessation in local galaxies. Weclassify 12 galaxies observed on two P-MaNGA plates as either centrallyquiescent (CQ) or centrally star-forming (CSF), according to whether D4000measured in the central spaxel of each datacube exceeds 1.6. For each galaxy wegenerate both 2D maps and radial profiles of D4000, EW(Hd_A) and EW(Ha). Wefind that CSF galaxies generally show very weak or no radial variation in thesediagnostics. In contrast, CQ galaxies present significant radial gradients, inthe sense that D4000 decreases, while both EW(Hd_A) and EW(Ha) increase fromthe galactic center outward. The outer regions of the galaxies show greaterscatter on diagrams relating the three parameters than their central parts. Inparticular, the clear separation between centrally-measured quiescent andstar-forming galaxies in these diagnostic planes is largely filled in by theouter parts of galaxies whose global colors place them in the green valley,supporting the idea that the green valley represents a transition betweenblue-cloud and red-sequence phases, at least in our small sample. These resultsare consistent with a picture in which the cessation of star formationpropagates from the center of a galaxy outwards as it moves to the redsequence.

P-MaNGA: Gradients in Recent Star Formation Histories as Diagnostics for Galaxy Growth and Death