Speaker
Michał Iglicki
(University of Warsaw)
Description
In this talk, I will discuss the so-called $t$-channel singularities that may occur when a given $t$-channel scattering process is mediated by a massive, stable particle on its mass shell.
After providing conditions for the singularity to occur and presenting several examples of SM and BSM processes afflicted by the issue, I will describe a regularization method based on thermal field theory.
Taking into account interactions between the $t$-channel mediator and the environment allows to assign an effective decay width to the mediator. Consequently, the singularity can be regularized using a resummed propagator.
Author
Michał Iglicki
(University of Warsaw)
