This is NUTS!

The Ultraviolet (UV) transient sky is one of the next frontiers in time-domain astrophysics with several space mission concepts planned for the middle of the decade. UV wavelengths are typically associated with hot phenomena, but we are focused on their use in measuring shock breakout and shock cooling from core-collapse supernovae (CCSNe) at very early times. These extreme events correspond to the shock emerging from the surface of the progenitor. If properly sampled, the UV peaks can be used to constrain properties of the progenitor stars, including the energy per unit mass of the SN ejecta and the stellar radius. Our HST survey of GOODS-S (#16706) will will represent the deepest and fastest UV time-domain survey to date. The survey will reach a depth of >26 mag AB over 73 square arcmin with a cadence of 2 days over 6 epochs out to a redshift of 1.3. Coordinated observations with the deep, ground-based Subaru Hyper Supreme Cam (HSC) SN survey will allow us to pinpoint the time and location of SNe.

Cycle 1 GO proposals for JWST (GO #1860 and 2666) programs will study dust in the supernova environment. A growing number of SN subclasses have recently begun to show evidence for mid-infrared emission in excess of the expected emission from standard radioactive component as the SN light-curve decays. The mid-IR excess is typically associated with dust, but the origin and heating mechanism of the dust remains relatively unconstrained. These observations will distinguish between newly formed ejecta dust and pre-existing dust in the circumstellar medium (CSM). Each result will have implications on our understanding of the late stages of pre-SN massive star evolution and the dust budget of the Universe.

The debate over the origin of stripped-envelope supernova explosions (i.e., SNe IIb, Ib, and Ic) continues to waver between single and binary stellar models. Binary star physics is important for our understanding of massive-star evolution and many areas of astrophysics, from galactic chemical evolution to gravitational wave detection, but the detailed physics (e.g., winds, mass exchange, rotation) remain unconstrained. Observationally, the field is past the point of considering individual, isolated systems. We are, for the first time, building a comprehensive, statistically complete sample of direct companion observations to measure the binary fraction, stellar type, and mass distribution. This exciting project is supported by HST GO 16165, 14075, 13648.