專題演講

2018/01/19(Fri)     11:00 -12:45    7th Floor(P7F)

Title

LHC physics with displaced vertices

Speaker

Dr. Giovanna Cottin

National Taiwan University

Abstract

Several models of new physics beyond the Standard Model (SM) predict the existence of massive, long-lived particles (LLPs) with macroscopic decays. These can be reconstructed as displaced vertices inside the LHC detectors. The lack of evidence of any new physics at the LHC motivates to perform these unconventional searches, such as looking for displaced vertices. Indeed, the null results at the LHC may point that the new physics is so feebly coupled to our SM that its signatures may have been overlooked or misidentified by searches not dedicated to LLPs. Therefore, LHC searches at this so-called lifetime frontier can be critical in the discovery of new physics.
In this talk, I will present two phenomenological studies of models with displaced vertices. I will comment on ongoing work in the recast of current ATLAS displaced searches to a left-right symmetric model with a long-lived sterile neutrino. Challenges and current limitations of displaced searches will be highlighted. I will also present a simple method for reconstructing particle masses in events with measurable displaced vertices, whose utility is motivated by models with displaced dark matter signatures at colliders.