The Full Picture: Determining the Ultra-Late Time MIR Flux Redistribution in SN 2021aefx
National Aeronautics and Space Administration James Webb Space Telescope General Observer Program-Cycle 3
Subaward to PSI from Space Telescope Science Institute
PI: James M DerKacy (Space Telescope Science Institute)
Non PSI Personnel: Chris Ashall (Co-Principal Investigator, University of Hawaii), Melissa Shahbandeh (Co-Principal Investigator, Space Telescope Science Institute), Peter Hoeflich (Co-Principal Investigator, Florida State University)
Project Description
Type Ia supernovae (SNe Ia) are the explosive, thermonuclear deaths of white dwarf stars in multi-star systems. Despite decades of intensive study, the true nature of their progenitors and the physical mechanism by which they explode are highly debated. SNe Ia provide crucial insights into other areas of astronomy, including: understanding sources of systematic errors in the use of SNe Ia as cosmological probes, the final phases of stellar evolution, and the origin and distribution of heavy elements. Enabled by the sensitivity of JWST, ultra-late MIR imaging with MIRI is key to addressing longstanding questions about flux redistribution to the MIR (estimated to be up to 80% of the total flux) and the bolometric luminosities of SN Ia at ultra-late times. We request 14.01 hours of MIRI imaging of SN 2021aefx at 1000 and 1150 days after maximum light to complete a legacy data-set which includes approved contemporaneous HST imaging and JWST NIRSpec and MIRI/LRS spectroscopy. The combined observations will obtain the first ever ultra-late time SED of a SN Ia from 0.4-28 um, enabling full use of accurate bolometric light curves. These data will: (1) reveal the amount of flux redistributed to the IR at late-times in SNe Ia and its time-dependence; (2) determine the masses and isotopic ratios of radioactive electron capture elements including 57Co and 55Fe; and (3) constrain the strength and evolution of the magnetic field in the SN. This ground-breaking data will provide the foundation upon which future studies of late-time SN Ia light curves are built. It will enormously enhance our understanding of heavy element production and the reliability of SNe Ia as distance indicators.
