Speaker
Description
We propose a new observational strategy to probe feebly interacting particles (FIPs) using dense, confined circumstellar material (CSM) around core-collapse supernovae. FIPs produced in the proto–neutron star can decay outside the star but still within the CSM prior to shock breakout, depositing visible energy that heats and ionizes the surrounding medium and forms a FIP-induced photosphere. This can generate a distinctive early-time precursor signal, approximately thermal (blackbody-like), that is complementary to conventional supernova cooling constraints. In this talk, I will present the underlying mechanism, characterize the expected precursor emission, and discuss how early-time supernova observations can be used to search for or constrain FIP scenarios.