Testing whether collapsars synthesize r-process elements

One of the open questions following the discovery of GW170817 is whether neutron star mergers are the dominant astrophysical sites of r-process production in the Universe. Simulations have shown that r-process elements are generated in the disk outflows of the rapidly rotating remnant black hole that is central to both neutron star mergers and collapsing massive stars (collapsars) — thus motivating theoretical predictions of observable r-process signatures in the near-infrared lightcurves of broadlined Ic supernovae associated with collapsars. We present the first observational campaign to test whether collapsars synthesize r-process elements, based on our systematic follow-up of Ic-BL SNe with the Zwicky Transient Facility and the Wide Infrared Camera. In this talk, I will share our observational constraints on the r-process ejecta mass and amount of mixing between the inner r-process material and outer Ni-56 ejecta from fits to state-of-the-art models. I will additionally discuss a few reddened IcBL SNe whose lightcurves appear consistent with r-process model predictions. Future near-infrared surveys like Roman and WINTER will lend valuable insights towards answering the open questions on astrophysical r-process sites.