Speaker
Description
In this talk, I will discuss a new strategy to probe feebly interacting particles using the circumstellar medium (CSM) surrounding core-collapse supernovae. New particles produced in the proto-neutron star can escape the stellar interior and deposit visible energy in the dense CSM through decays before shock breakout. This energy injection heats and ionizes the CSM, forms a new particle-induced photosphere, and can generate a distinctive precursor blackbody emission. Taking kinetically mixed dark photons as a benchmark model, I will show how early-time observations of SN 2023ixf constrain such pre-breakout emission and exclude previously unexplored regions of MeV-scale dark photon parameter space. I will also discuss how particle-induced dust sublimation in the outer CSM provides a robust diagnostic for future nearby supernovae, opening a new observational window on dark-sector physics.