Sum rules for extended electroweak symmetry breaking sectors

Sum rules for extended electroweak symmetry breaking sectors
Ryo Nagai, Tohoku
Photo of Ryo Nagai
Date and time: Tue, Nov 28, 2017 - 2:30pm
Location: LGRT 419B
Category: ACFI Seminar
Abstract:

I will discuss the extended electroweak symmetry breaking scenarios in model independent manner. The key is “unitarity sum rules”. One of the important roles of the SM Higgs boson is to keep longitudinal electroweak gauge boson scattering (VV scattering) amplitudes perturbatively unitary in high energy limit. However, if the Higgs coupling deviates from the SM prediction, the perturbative unitarity might be broken down at the certain energy scale. In order to maintain the perturbative unitarity with anomalous higgs couplings, we need new particle(s) whose couplings are tuned to cancel a bad behavior of VV scattering amplitudes. The required conditions are called “unitarity sum rules”. In this talk, we apply the sum rules to investigate physics beyond the standard model. References: https://arxiv.org/abs/1409.1709 , https://arxiv.org/abs/1607.03706