Constraining Supernova Progenitors through Strong Lensing in the Rubin LSST Era

• Applicants: Professorin Sherry H. Suyu, Ph.D.; Dr. Stefan Taubenberger
• Subject Area: Astrophysics and Astronomy
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 569305999

The nature of supernova (SN) progenitors remains a largely debated question to this day, as are the mechanisms by which different types of stars explode. One major hurdle is the lack of appropriate observational data, both sufficiently close in time to the explosion and at sufficiently short wavelengths (rest-frame UV), which exhibit the largest signatures of the exploding star (radius, surface chemical composition, and pre-explosion mass loss) and its potential binary companion. A strongly lensed SN offers a unique opportunity to access this observational sweet spot, as the galaxy lens will produce multiple images of the background SN that appear at different times. When such an event is detected based on the first appearing SN image, one can use the predicted time delays between the multipleimages to catch the SN right at the moment of its next appearance, and hence access the first hours/days of its evolution. Moreover, the magnification of lensed SNe enables the discovery and follow-up of high-redshift events, whose rest-frame UV radiation can be observed with ground-based facilities at optical wavelengths. The upcoming Vera Rubin Observatory will discover up to ~100 lensed SNe of all types with sufficiently long and accurately determined time delays during its ten-year Legacy Survey of Space and Time (LSST). Our three-year project will allow us to obtain the earliest rest-frame UV observations of SNe ever made. Our complementary expertise in deep-learning classification, lens and SN modelling, combined with our access to LSST data and follow-up facilities, will yield unprecedented constraints on the progenitors of all types of SNe shortly after they explode.

• DFG Programme: Research Grants
• International Connection: France
• Cooperation Partners: Dr. Stéphane Blondin; Dr. Luc Dessart