Center for Theoretical Physics of the Universe (CTPU)

Sum rules for extended electroweak symmetry breaking sectors

by Dr Ryo Nagai (Tohoku University)

CTPU Seminar Room

CTPU Seminar Room

Fourth floor IBS Building, 55, Expo-ro, Yuseong-gu, Daejeon, Korea, 34126

I plan to discuss the extended electroweak symmetry breaking (EWSB) scenarios by applying “unitarity sum rules”, which are required conditions on low-energy coefficients to ensure unitarity. The sum rules tell us nontrivial relationship between the properties of new particles/phenomena and the low-energy observables such as the 125GeV Higgs signal strengths (coupling strengths). In this talk, we discuss the implications of the sum rules in two kinds of extended EWSB scenarios : (i) EWSB with extra Higgs bosons (based on Ref. [1]) and (ii) EWSB with extra spin-1 particles (based on Ref. [2]).

[1] R. Nagai, M. Tanabashi and K. Tsumura, ``Does unitarity imply finiteness of electroweak oblique corrections at one loop? Constraining extra neutral Higgs bosons,'' Phys. Rev. D91 (2015) no.3, 034030 [arXiv:1409.1709 [hep-ph]].

[2] T. Abe and R. Nagai, ``Classification of simple heavy vector triplet models,''  Phys. Rev. D95 (2017) no.7, 075022 [arXiv:1607.03706 [hep-ph]].