Simulating the Angular Distribution of Cherenkov Radiation in Thick Media

arXiv:2509.16283v1 Announce Type: new
Abstract: We present a study of the emission of Cherenkov radiation in thick media, explore the limitations of the simulation tools currently in use in particle and nuclear physics, and propose a method for overcoming these limitations. We start with a derivation of the Cherenkov power spectrum and its angular profile, accounting for interference of the radiation emitted, in contrast with commonly used tools that assume perfect coherence. We then study the impact that the path of electrons through a medium has on the angular profile of Cherenkov light. Finally, we devise a model that can introduce these effects in Geant4 and tune it to explain calibration data from the water-phase of SNO+. We find that the tuned model significantly improves the agreement between data and simulation, so we provide it for its wider use.