Enhancement of H -> gamma gamma in SU(5) model with 45_H plet

Abstract

We show that the low energy effective model derived from SU(5) with 45-plet Higgs can account for the recently reported enhanced diphoton decay rate of the Standard Model (SM)-like Higgs with mass about 125 GeV. This model extends the SM by an extra Higgs doublet and color-octet scalar doublet. We show that the charged octet scalars are not severely constrained by flavor changing neutral current and can be light. However, the K^0-\bar{K}^0 mixing implies that the neutral octet-scalar mass should be larger than 400 GeV for \tanβ~ O(1). The role of charged octet scalar in the loop of Higgs decay into diphoton is investigated . We point out that the most significant impact of this model on the diphoton decay width comes from the suppression of top-quark coupling with SM-like Higgs or even flipping its sign that leads to important enhancement in Γ(h -> gamma gamma). We also study the implications of the neutral octet-scalar contributions to the gluon fusion Higgs production cross section in alleviating the apparent tension between enhancement of diphoton decay rate and suppression of σ(gg -> h).

21 pages, 11 Figures

References in corpus (15)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Color-octet scalars at the LHC
• Search for narrow resonances and quantum black holes in inclusive and b-tagged dijet mass spectra from pp collisions at sqrt(s) = 7 TeV
• Fermion Masses and the UV Cutoff of the Minimal Realistic SU(5)
• Unification versus proton decay in SU(5)
• Proton Stability, Dark Matter and Light Color Octet Scalars in Adjoint SU(5) Unification
• Grand Unification and Light Color-Octet Scalars at the LHC
• The SM extension with color-octet scalars: diphoton enhancement and global fit of LHC Higgs data
• Higgs Uncovering Light Scalar Remnants of High Scale Matter Unification
• Pair Production of Color-Octet Scalars at the LHC
• Color Octet Scalar Bound States at the LHC
• Electroweak phase transition in an extension of the Standard Model with scalar color octet
• Color-octet scalars at the LHC
• Precise predictions for Higgs production in models with color-octet scalars

Cited by in corpus (12)

• Fermion masses and mixings in an $SU(5)$ grand unified model with an extra flavor symmetry
• Adjoint $SU(5)$ GUT model with $T_7$ flavor symmetry
• A renormalizable left-right symmetric model with low scale seesaw mechanisms
• Universal Inverse seesaw mechanism as a source of the SM fermion mass hierarchy
• Phenomenological Aspects of TeV Scale Alternative Left-Right Model
• Fermion masses and mixings and $g-2$ muon anomaly in a 3-3-1 model with $D_4$ family symmetry
• Phenomenology of SU(5) low-energy realizations: the diphoton excess and Higgs flavor violation
• An extended 3-3-1 model with two scalar triplets and linear seesaw mechanism
• TeV-scale leptoquark searches at the LHC and their E${}_6$SSM Interpretation
• SU(5) Octet Scalar at the LHC
• Phenomenological aspects of the fermion and scalar sectors of a $S_4$ flavored 3-3-1 model
• CP Asymmetry in $\tau \to K\pi {\nu }_{\tau }$ within Non-Minimal $SU(5)$