Pair-Instability Supernovae in the Era of Next-Generation Surveys: Observational and Theoretical Frontiers
Speaker: Steve Schulze (Weizmann Institute of Science)
Abstract:
The fate of the most massive stars remains one of the central questions in stellar evolution and time-domain astronomy. Pair-Instability Supernovae (PISNe) and Pulsational PISNe (PPISNe), the predicted endpoints of stars above roughly 95 solar masses, offer a rare opportunity to test our understanding of stellar physics and to glimpse the processes that shaped the early Universe. These explosions likely marked the deaths of Population III stars and contributed to the chemical enrichment and dust content of the first galaxies.
As facilities such as the Rubin Observatory and the Euclid, James Webb and Roman Space Telescopes begin to survey the dynamic and static high-redshift Universe (z ~ 2-10), identifying bona fide (P)PISNe becomes both crucial and increasingly challenging. Spectroscopic follow-up is limited, even for bright candidates, and several other explosion channels can mimic PISN-like signatures. This may lead to contaminated samples and biased event-rate estimates, with consequences for our broader understanding of stellar and galaxy evolution.
In this talk, I will review insights from the most promising PPISN and PISN candidates of the past decade, emphasising the key observational challenges and theoretical uncertainties that affect their interpretation. I will discuss the multi-wavelength diagnostics and observing strategies needed to identify these rare transients in forthcoming surveys. I will also outline where current progenitor and explosion models fall short, and highlight areas where theoretical progress is urgently required to interpret candidates with confidence and to anticipate the types of PISN-like events that next-generation facilities may uncover. By combining these observational lessons with pressing theoretical questions, I will outline a path to identify (P)PISNe and constrain the physics of the most extreme stellar explosions.