MSc. Subrata Samanta

What can LHC data tell us about Higgs triplet models?

I will discuss the phenomenology of the triplet scalar extensions of the Standard Model in light of Large Hadron Collider data. Triplet scalars can contribute to electroweak symmetry breaking and modify Higgs couplings, providing distinctive probes of physics beyond the Standard Model (SM). In particular, the Georgi-Machacek (GM) model allows a sizable triplet vacuum expectation value while remaining consistent with experimental data and has rich collider phenomenology. Although the GM model is well motivated at tree level, incorporating radiative corrections is essential for obtaining precise predictions beyond leading order. I will therefore formulate a consistent one-loop renormalization framework for the GM model. The renormalization of this model is phenomenologically important when triggered by operators that are absent at the tree level due to the global symmetry. In comparison with the SM, this model requires an additional input parameter to completely parametrize the electroweak precision observables at one-loop. Finally, I will present the constraints on the GM model parameter space obtained from a global Bayesian fit.