Michael Brown (Monash University), Kevin Pimbblet (University of Hull)
Passive spiral galaxies allow us to identify when and where quenching mechanisms truncate star formation whilst preserving galaxy disks.
We use an absence of mid-infrared dust emission and nebular emission lines to identify and confirm a sample of 51 passive spiral galaxies (Fraser-McKelvie et al., 2016, MNRAS, 462,11). Our passive spiral sample spans a range of stellar masses and environments, ruling out any one traditional quenching mechanism.
Significantly, 74% of our passive spiral sample are barred, many of which feature ansae (or ‘handles’ at the ends of the bar). This is much higher than a mass, z, and T-type-matched comparison sample (36%), leading us to postulate that bars, or the mechanism that creates them, are responsible for quenching a large proportion of the passive spiral population.
In order to determine the quenching pathways of the non-barred passive spirals we separate our sample by mass. All low mass (M