Shocks and expanding ejecta in Supernova 1987A

Supernovae (SNe) play crucial roles in the chemical and dynamical evolution of galaxies; they are sources of kinetic energy and elements, and provide and destroy dust. With JWST, these fundamental questions for SNe will be tackled: How do core collapse SNe explode? How do the SN blast waves impact the ambient gas and destroy dust?

We propose to obtain high-sensitivity and high angular-resolution NIRCam images of SN 1987A, which at a distance of 50 kpc is the nearest SN explosion detected in the last 400 years. Since the explosion, the fastest part of the blast wave has overtaken the circumstellar ring, which consists of material expelled from the progenitor star when it was in a red-supergiant phase about 20,000 years ago. Deep NIRCam images, including with the [Fe II] 1.64um filter, can identify for the first time the location of the current shocked region beyond SN 1987A's ring.

The blast wave and reverse shocks shatter and sputter dust grains into smaller fragments and collisionally heat them to high temperatures. NIRCam will be the able to spatially resolve hot dust and pinpoint the hot dust locations with respect to [Fe II]-traced shocks. Shock models including dust destruction will be used to evaluate the efficiency of the real time dust destruction by the SN blast wave.

H2 images obtained with NIRCam can resolve both the distribution and excitation of molecular hydrogen in the inner ejecta. They can trace the posited mixing of the hydrogen envelope deep into the ejecta at the time of SN explosion, thereby constraining the SN explosion model, which predicts mixing efficiencies that depend on the explosion energy.