There was a star-forming galaxy that was quenched

Cluster galaxies are subject to a whole range of processes and interactions that dramatically change their properties. To shed light on these issues, we analyze the most homogeneous and complete local cluster galaxy survey to date: WINGS/OmegaWINGS, and use stellar population synthesis techniques to obtain properties such as stellar mass, stellar ages, SFR, and SFH.

Our results show that, although the cluster environment eventually shuts off the star formation, some mechanisms might instead enhance it temporarily, i.e., ram pressure and close encounters with other galaxies. In this picture, it is crucial to take morphology into account: while cluster spirals do follow the main sequence, early types still display some level of star formation, likely triggered by hydrodynamic interactions with other galaxies. Finally, the local environment dominates the stellar evolution, while the global cluster is likely a secondary agent.