LHC diphoton and Z+photon Higgs signals in the Higgs triplet model with Y = 0

Abstract

Abstract:We study the implications of the LHC diphoton and Z+photon Higgs signals on the Higgs triplet model with Y=0, which predicts two neutral CP-even Higgs bosons h, H and a pair of charged Higgs H ± . We discuss three different scenarios: (i) the observed boson is the light Higgs boson h; (ii) it is the heavy Higgs boson H; (iii) the observed signal is from the almost degenerate h and H. We find that the inclusive Higgs diphoton rates in the first two scenarios can be enhanced or suppressed compared to the SM value, which can respectively fit the ATLAS and CMS diphoton data within 1σ range. The inclusive ZZ * rates are suppressed, which are outside 1σ range of ATLAS data and within 1σ range of CMS data. Meanwhile, another CP-even Higgs boson production rate can be suppressed enough not to be observed at the collider. For the third scenario, the Higgs diphoton rate is suppressed, which is outside 1σ range of ATLAS data, and the ZZ * rate equals to SM value approximately. In addition, we find that the two rates of h → γγ and h → Zγ have the positive correlations for the three scenarios.

Vector-like quarks with a scalar triplet

“…However, since an inert real scalar triplet does not mix with the SM Higgs doublet, tree-level modifications to the model's couplings do not exist. In particular, the couplings involving the scalar bosons are given by [29] (10) where g is the SU(2) W gauge coupling. In the case of an inert real triplet extension of the SM, the absence of mixing with the SM-like Higgs doublet results in the absence of couplings between η 0 /η ± and fermions, and therefore no additional contributions to the Zbb vertex are present [32].…”

“…is the scalar potential [28,29], and the covariant derivatives are the standard SU(2) W × U (1) Y , as in the SM.…”

“…The possibility of extending the SM with a real SU(2) W triplet scalar has been extensively studied [21][22][23][24][25][26][27][28][29][30] since such extensions generally lead to suppressed contributions to electroweak precision observables (EWPO). The scalar Lagrangian for a toy model including all possible gauge invariant combinations of a Higgs doublet, H , and an SU(2) W triplet, , given by…”

Radiative neutrino mass with scotogenic scalar triplet

“…In the present variant of the model the state with mass 125 GeV discovered at the LHC corresponds to the SM higgs and the measurement of an enhancement R γγ [1,2] may reveal the existence of the charged scalars or put constrains on the parameters of our model. Recent study [18] scrutinizes the LHC diphoton signal in purely hypercharge-zero scalar triplet extension of the SM.…”

Two-step electroweak symmetry-breaking: theory meets experiment

“…However, they consider a dimension-5 effective operator involving the triplet that significantly modifies the phenomenology relative to the minimal triplet model that we study. The general phenomenology of minimal hypercharge-zero SU(2) triplet scalar extensions has been studied extensively [18][19][20][21], with a significant focus on the prospects of having the neutral component of the triplet be stable and thus provide some or all of the dark matter (DM) density [22][23][24][25][26][27][28].…”