Constraining the Georgi-Machacek model with a light Higgs boson
Amine Ahriche
Abstract
In this work, we investigate the viability of a light Higgs ($\ensuremath{\eta}$) scenario in the Georgi-Machacek (GM) model, where we consider all theoretical and experimental constraints such as the perturbativity, vacuum stability, unitarity, electroweak precision tests, the Higgs diphoton and undetermined decays and the Higgs total decay width. In addition, we consider more recent experimental bounds from the searches for doubly charged Higgs bosons in the vector boson fusion channel ${H}_{5}^{++}\ensuremath{\rightarrow}{W}^{+}{W}^{+}$, Drell-Yan production of a neutral Higgs boson $pp\ensuremath{\rightarrow}{H}_{5}^{0}(\ensuremath{\gamma}\ensuremath{\gamma}){H}_{5}^{+}$, and for the light scalars at LEP ${e}^{\ensuremath{-}}{e}^{+}\ensuremath{\rightarrow}Z\ensuremath{\eta}$, and at ATLAS and CMS in different final states such as $pp\ensuremath{\rightarrow}\ensuremath{\eta}\ensuremath{\rightarrow}2\ensuremath{\gamma}$ and $pp\ensuremath{\rightarrow}h\ensuremath{\rightarrow}\ensuremath{\eta}\ensuremath{\eta}\ensuremath{\rightarrow}4\ensuremath{\gamma},2\ensuremath{\mu}2\ensuremath{\tau},2\ensuremath{\mu}2b,2\ensuremath{\tau}2b$. By combining these bounds together, we found a parameter space region that is significant as the case of the SM-like Higgs to be the light $CP$-even eigenstate, and this part of the parameter space would be tightened by the coming analyses.