Speaker
Description
In-medium properties of particles differ significantly from vacuum ones, due to finite temperature and density effects. For example, the photon in a plasma acquires an effective mass and can thus decay into neutrinos, a process forbidden in vacuum. Finite temperature and density effects are also crucial for accurate Beyond the Standard Model (BSM) phenomenology. Indeed, processes involving BSM particle are often studied inside a medium, for example in stars or in the primordial plasma. However, many calculations still rely on the vacuum particle physics treatment, which can miss important effects like new decay channels and resonances.
In this talk, I will present a comprehensive procedure to take into account in-medium effects for BSM physics phenomenology. I will focus on qualitatively new in-medium effects, such as resonances and interference diagrams with the medium particles. I will also present concrete applications of these effects in models of scalar BSM particles.