We consider the most general set of SU (2) × U (1) invariant CP-violating operators of dimension six, which contribute to V V h interactions (V = W, Z, γ). Our aim is to constrain any CP-violating new physics above the electroweak scale via the effective couplings that arise when such physics is integrated out. For this purpose, we use, in turn, electroweak precision data, global fits of Higgs data at the Large Hadron Collider and the electric dipole moments of the neutron and the electron. We thus impose constraints mainly on two-parameter and three-parameter spaces. We find that the constraints from the electroweak precision data are the weakest. Among the existing Higgs search channels, considerable constraints come from the diphoton signal strength. We note that potential contribution to h → γZ may in principle be a useful constraining factor, but it can be utilized only in the high energy run. The contributions to electric dipole moments mostly lead to the strongest constraints, though somewhat fine-tuned combinations of more than one parameter with large magnitudes are allowed. We also discuss constraints on gauge boson trilinear couplings which depend on the parameters of the CP-violating operators .Although the discovery of "a Higgs-like boson" at the Large Hadron Collider (LHC) has been a refreshing development [1,2], there is no clear signal yet for physics beyond the standard model (SM). It is therefore natural that physicists are trying to wring the last drop out of the Higgs sector itself, in attempts to read fingerprints of new physics.One approach is to examine all available data in terms of specific new models, such as supersymmetry or just additional Higgs doublets. In the other approach, one can take a model-independent stance, parametrize possible modifications of the interaction terms of the Higgs with pairs of SM particles, and examine them in the light of the available data. Such modifications can again be of two types. In the first category, they are just multiplicative modifications of the coupling strengths, the Lorentz structures remaining the same as in the SM. Constraints on such modifications have already been derived from the available Higgs data [3][4][5][6][7]. In the second class, one considers additional operators with new Lorentz structures satisfying all symmetries of the SM [8][9][10][11][12][13][14][15]. Gauge invariance of such operators in their original forms may be expected, since they are obtained by integrating out new physics that is just above the reach of the present round of experiments. Sets of such higher-dimensional operators contributing to the effective coupling of the Higgs to, say a pair of electroweak vector bosons have been studied extensively. Here it makes sense to include only SU (2) × U (1) invariant operators in one's list to start with, because the yet unknown new physics lies at least a little above the electroweak symmetry breaking scale. A host of such gauge invariant higher-dimensional operators have been, and are being, analyzed with considerable...

We analyze the prospects of reconstructing the mass of a heavy charged Higgs boson in the context of a Type X two-Higgs doublet model where a light pseudoscalar A in the mass range 40 − 60 GeV is phenomenologically allowed, and is in fact favoured if one wants to explain the muon anomalous magnetic moment. The associated production of charged Higgs with the pseudoscalar A and subsequent decay of the charged Higgs into a W and A, is found to be our relevant channel. The branching ratio for H + → W + A with M H + ∼ 200 GeV, is close to 50%. The hadronic decay of the W boson, coupled with the leptonic decays of A into a tau and muon pair, help in identifying the charged Higgs. The neutral heavy Higgs, being degenerate with the charged Higgs for most of the allowed parameter space of the model, also contributes to similar final states. Thus both of these particles are reconstructed within a band of about 10 GeV.

We investigate the detectability as well as reconstructibility of a light pseudoscalar particle A, of mass in the 50 -60 GeV range, which is still allowed in a Type-X (lepton-specific) two-Higgs doublet scenario. Such a pseudoscalar can be pair-produced in the decay h → AA of the 125 GeV scalar h. The light pseudoscalar in the aforementioned range, helpful in explaining the muon anomalous magnetic moment, has not only substantial branching ratio in the τ + τ − channel but also one of about 0.35% in the µ + µ − final state. We show how to faithfully reconstruct the A mass using the µ + µ − mode, and establish the existence of a pseudoscalar around 50 -60 GeV, using the process pp → h → AA → µ + µ − τ + τ − . This is the most reliable way of reconstructing the light A mass, with a statistical significance that amounts to discovery, with a few hundred (or less) fb −1 of integrated luminosity.

We consider the observable effects of CP-violating anomalous ZZh interaction arising from gauge invariant dimension-6 operators at the Large Hadron Collider (LHC), with the purpose of distinguishing them from not only the standard model effects but also those of CP-even anomalous interactions of similar nature. The postulation of a gauge invariant origin makes various couplings of this kind interrelated. The updated constraints from the LHC as well as limits from neutron and electron dipole moments are used in selecting the benchmark interaction strengths. We use some asymmetry parameters that have no contribution from standard or CP-even anomalous interactions. Parton showering and detector level simulation is included to make our analysis as realistic as possible. On the whole, we conclude that gauge invariant interaction of strength ≥ 40/TeV 2 can be successfully isolated using integrated luminosities in the 1.5-3.0 ab −1 range.

The flavorful Z model with its couplings restricted to the left-handed second generation leptons and third generation quarks can potentially resolve the observed anomalies in R K and R K *. After examining the current limits on this model from various low-energy processes, we probe this scenario at 14 TeV high-luminosity run of the LHC using two complementary channels: one governed by the coupling of Z to b-quarks and the other to muons. We also discuss the implications of the latest LHC high mass resonance searches in the dimuon channel on the model parameter space of our interest.