Dust, Mass Loss and Explosions of Massive Stars in the MIR

Core-collapse supernovae (CC SNe) are explosions of massive >10 Msun. CC SNe with hydrogen rich envelopes, type II SNe (SNe II), are the most common stellar explosions and are the main producers of heavy elements in the universe. As a result the study of these cosmic explosions probes the chemical evolution of the universe, sheds light on the composition of dust in our solar system, and ultimately the genesis of life. Moreover, molecules have been observed in the ejecta that form dust and determine which elements are present in interstellar gas and which are tied up in cosmic dust. Despite the prevalence of CC SNe, their physics is not well understood. The explosion of CC SNe takes seconds, whereas the SN light emitted and observed from the extended envelope evolves on timescales of weeks to years. However, the explosion mechanism can be determined by late-time observations of the SN when the core region is exposed. We request 22.1 h of non-disruptive ToO time to obtain 3 mid-infrared (MIR) and 3 near-infrared (NIR) spectra of a SN II between 50 and 200 days from explosion. This program will answer fundamental questions about the progenitor and explosion physics and the life-cycle of elements. The MIR has many isolated lines and JWST will obtain high resolution and signal-to-noise data which is necessary to determine: 1) the pre-explosion mass loss history, 2) the distribution of elements produced during the stellar evolution and explosion, 3) the possible role of CC SNe in the production of r-process elements, 4) the formation of new, warm dust via SiO, 5) and whether the early cold carbon-dust is primordial or freshly formed.