相关论文: The "forgotten" decay S -> Z+h as a CP analyzer

LHC has reported tantalizing hints for a Higgs boson of mass 125 GeV decaying into two photons. We focus on two-Higgs-doublet Models, and study the interesting possibility that the heavier scalar (H) has been seen, with the lightest scalar…

The existence of a 750 GeV di-photon spin-0 resonance $S$ would imply the additional presence of new particles beyond the Standard Model, coupling directly to $S$ and electromagnetically charged. For an $SU(2)_{\mathrm{L}}$ singlet $S$, we…

The $Z\to \gamma \gamma$ and $Z\to gg$ decays are studied in the context of the renormalizable version of the Standard Model Extension. The $CPT$-odd $\bar{\psi}\gamma_5 \gamma^\mu b_\mu\psi$ bilinear interaction, which involves the…

Motivated by the tantalizing excesses recently reported in the di-photon invariant mass spectrum at the LHC, we scrutinize some implications of scalar di-photon resonances in high energy proton-proton collisions. In particular, indications…

We study possible deviations from the Standard Model in the reaction $e^+e^- \to Z\phi$, where $\phi$ denotes a spinless neutral boson. We show how the $Z$ decay angular correlation can be used to extract detailed information on the $\phi$…

In light of the discovery of a Standard Model (SM)-like Higgs boson ($h$) at the LHC, we investigate the top quark to Higgs boson transition $t\rightarrow W^{*}bh$, which is the leading $t\to h$ decay mode in the SM. We find the decay…

New Physics models with either an elementary or composite origin are often associated with a similar imprint in a direct search at colliders, case in point being the production of a light pseudoscalar in association with a monochromatic…

In view of the recent diboson resonant excesses reported by both ATLAS and CMS Collaborations, we suggest that a new weak singlet pseudo-scalar particle, $\eta_W$, may decay into two weak bosons while being produced in gluon fusion at the…

Assuming a heavy electroweak singlet scalar, which couples to the Standard Model gauge bosons only through loop-induced couplings, SU(2)_L x U(1)_Y gauge invariance imposes interesting patterns on its decays into electroweak gauge bosons,…

The evidence for a new singlet scalar particle from the 750 GeV diphoton excess, and the absence of any other signal of new physics at the LHC so far, suggest the existence of new coloured scalars. To study this possibility, we propose a…

The decay of the mediator particle into standard model (SM) particles plays a significant role in exploring the dark sector scenario. We consider such a decay, taking the dark photon mediator as an example that mixes with the SM photon. We…

We analyze the coupling of CP-even and CP-odd Higgs bosons to a photon and a Z boson in extensions of the Standard Model. In particular, we study in detail the effect of charged Higgs bosons in two-Higgs doublet models, and the contribution…

Nine statistically significant decay channels are observed in LHC data around a mass of 650 GeV. We interpret three of them as coming from a 20 GeV wide resonance observed in $e^+e^-$ , 2 photons and ZZ which could be a $J=2$ Kaluza Klein…

The recent diphoton excess at the LHC has been explained tentatively by a Standard Model (SM) singlet scalar of 750 GeV in mass, in the association of heavy particles with SM gauge charges. These new particles with various SM gauge charges…

The decay $B^0_s\to\mu^+\mu^-$ is a key probe for the search of physics beyond the Standard Model. While the current measurements of the corresponding branching ratio agree with the Standard Model within the uncertainties, significant…

We propose that the diphoton resonance signal indicated by the recent LHC data might also arise from the pair productions of vector-like heavy down-type quarks with mass around $750$ GeV and above. The vector-like quark decays into an…

We introduce a physical scalar sector in a SU(2)xU(1) electroweak theory in which the gauge group is realized non linearly. By invoking theoretical as well as experimental constraints, we build a phenomenologically viable model in which a…

A search for the resonant production of a heavy scalar $X$ decaying into a lighter scalar $S$ and a Higgs boson, through the process $X \rightarrow S (\rightarrow b \bar{b})H ( \rightarrow \gamma\gamma)$, where the two photons are…

Searching for heavy neutral gauge bosons Z', predicted in extensions of the Standard Model based on a U(1)' gauge symmetry, is one of the challenging objectives of the experiments carried out at the Large Hadron Collider. In this paper, we…

New particles at the TeV-scale may have sizeable decay rates into boosted Higgs bosons or other heavy scalars. Here, we investigate the possibility of identifying such processes when the Higgs/scalar subsequently decays into a pair of W…