Conor Ransome (Harvard)
Type IIn Supernovae: Diversity, Hosts and Progenitors.

The enigmatic type IIn class of supernovae (SNIIn) claim a vast territory on the timescale-luminosity phase-space. These transients are characterised by persistent signatures of interaction with a pre-existing, dense, slow, and often massive circumstellar medium made up of mass lost from the progenitor by massive winds and/or non-terminal eruptions. This however, is where the inter-class similarities end as SNeIIn are highly heterogenous in terms of their observed photometric and spectroscopic features, some even turn out to be impostors! In this talk, I will outline my efforts to constrain the possible progenitor paths. Firstly, I will discuss studies of the hosts and local environments of SNeIIn and the implications of the distributions of these transients. I will also discuss the largest systematically modeled sample of SNeIIn, the inferred parameters of the population and the distribution of mass-loss rates which have important ramifications for the possible progenitors.