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