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 have investigated the effect of group environment on residual starformation in galaxies, using Galex NUV galaxy photometry with the SDSS groupcatalogue of Yang et al. (2007). We compared the (NUV $- r$) colours of groupedand non-grouped galaxies, and find a significant increase in the fraction ofred sequence galaxies with blue (NUV $- r$) colours outside of groups. Whencomparing galaxies in mass matched samples of satellite (non-central), andnon-grouped galaxies, we found a > 4{\sigma} difference in the distribution of(NUV $- r$) colours, and an (NUV $- r$) blue fraction $> 3{\sigma}$ higheroutside groups. A comparison of satellite and non-grouped samples has found theNUV fraction is a factor of $\sim2$ lower for satellite galaxies between$10^{10.5}M_{\bigodot}$ and $10^{10.7}M_{\bigodot}$, showing that higher massgalaxies are more able to form stars when not influenced by a group potential.There was a higher (NUV $- r$) blue fraction of galaxies with lower Sersicindices (n < 3) outside of groups, not seen in the satellite sample. We haveused stellar population models of Bruzual & Charlot (2003) with multiple burst,or exponentially declining star formation histories to find that many of the(NUV $- r$) blue non-grouped galaxies can be explained by a slow ($\sim 2$ Gyr)decay of star formation, compared to the satellite galaxies. We suggest thattaken together, the difference in (NUV $- r$) colours between samples can beexplained by a population of secularly evolving, non-grouped galaxies, wherestar formation declines slowly. This slow channel is less prevalent in groupenvironments where more rapid quenching can occur.

NUV signatures of environment driven galaxy quenching in SDSS groups