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 use GALEX ultraviolet and WISE 22 micron observations to investigate thecurrent star formation activity of the optically-red spirals recentlyidentified as part of the Galaxy Zoo project. These galaxies were accuratelyselected from the Sloan Digital Sky Survey in order to be pure discs with lowor no current star formation activity, representing one of the bestoptically-selected samples of candidate passive spirals. However, we show thatthese galaxies are not only still forming stars at a significant rate >= 1M_sun/yr but, more importantly, their star formation activity is not differentfrom that of normal star-forming discs of the same stellar mass (M* >= 10^10.2M_sun). Indeed, these systems lie on the UV-optical blue sequence, even withoutany corrections for internal dust attenuation, and they follow the samespecific star formation rate vs. stellar mass relation of star-forminggalaxies. Our findings clearly show that, at high stellar masses, opticalcolours do not allow to discriminate between actively star-forming and trulyquiescent systems.

Are passive red spirals truly passive? - The current star formation activity of optically-red disc galaxies