Related papers: Hypergeometric presentation for one-loop contribut…
We study the rare decay $Z_H \rightarrow H^0 \gamma$ at $\mathcal{O}(\alpha_{{\rm ew}}^{3}\alpha_s)$ accuracy including two-loop QCD corrections in the context of the littlest Higgs model (LHM) without $T$-parity. We revisit analytically…
The decay of the Higgs boson into two photons is examined in a model-independent way within the effective Lagrangian approach. Contribution of one-loop diagrams including SU(2) x U(1) invariant dimension-six bosonic operators is evaluated…
For the search for additional Higgs bosons in the Minimal Supersymmetric Standard Model (MSSM) as well as for future precision analyses in the Higgs sector a precise knowledge of their decay properties is mandatory. We evaluate all two-body…
Higgs boson radiative decays of the form $H\rightarrow f\bar{f}\gamma$ are calculated in the Standard Model using the complete one-loop expressions for the decay amplitudes. Contributions to the radiative width from leptons and light quarks…
The decay $H\to \ell^+\ell^- \gamma$, $\ell=e,\mu$, receives contributions from $H\to Z[\to \ell^+\ell^-] \gamma$ and a non-resonant contribution, both of which are loop-induced. We describe how one can separate these sub-processes in a…
We point out that the one-loop amplitude of the $h^0\rightarrow\gamma\gamma$ decay is gauge invariant owing to a particular relation between the trilinear couplings and the Higgs boson mass. This relation follows only from the gauge…
We evaluate the one-loop prefactor in the false vacuum decay rate in a theory of a self interacting scalar field in 3+1 dimensions. We use a numerical method, established some time ago, which is based on a well-known theorem on functional…
We present a detailed analysis of the Higgs boson decays $h\rightarrow Z \gamma$ and $h\rightarrow m_V Z$ in the $U(1)_X$SSM, with $m_V$ denoting the meson ($\omega,\rho,\phi,J/{\psi},\Upsilon$). Using the effective Lagrangian method, we…
There has been a controversial recent claim that the standard result on the Higgs to two photon decay rate is incorrect, with the use of dimensional regularization fingered as the alleged culprit. Given the great importance of the $H\to…
In the minimal supersymmetric standard model the decay $h^0 \to A^0A^0$ of the light neutral scalar $h^0$ is kinematically allowed for low values of $\tan\beta$ when radiative corrections to the neutral Higgs masses are taken into account.…
Using the most recent results of CMS and ATLAS, we study the Higgs decays to $\gamma\gamma$ and $Z\gamma$ in the scenario where the two CP even Higgs predicted by the type II seesaw model (HTM) are close to mass degenerate with a mass near…
Decay amplitude of $H \to \gamma Z$ process via one $W$ loop in the unitary gauge is presented. The divergent integrals including those of high divergence orders typical of unitary gauge are arranged to cancel to get the electromagnetic…
We examine the contribution of W boson loops to the amplitude of the process H --> \gamma \gamma within the dispersion relation approach, taking up an issue raised in this context recently. We show that the non-vanishing limit of the…
A light vector boson, Z_d, associated with a "dark sector" U(1)_d gauge group has been introduced to explain certain astrophysical observations as well as low energy laboratory anomalies. In such models, the Higgs boson may decay into…
We explore the phenomenology of virtual spin-1 contributions to the h to gamma gamma and h to Z gamma decay rates in gauge extensions of the standard model. We consider generic lorentz and gauge invariant vector self-interactions, which can…
We compute three-loop corrections to the process $gg\to HH$ originating from one-particle reducible diagrams. This requires the computation of two-loop corrections to the gluon-gluon-Higgs vertex with an off-shell gluon. We describe in…
The one-loop contributions to the branching ratios for leptonic tau decays are calculated in the CP conserving 2HDM(II). We found that these one-loop contributions, involving both neutral and charged Higgs bosons, dominate over the…
We explore the phenomenology of a fermiophobic Higgs: a Higgs whose couplings to fermions are suppressed. We calculate the branching ratios of a Higgs decaying to $\gamma\gamma$, $W^*W^*$, $Z^*Z^*$, $Zb\bar b$, $Z\gamma$, $\gamma b\bar b$,…
We compute the two-loop corrections to the massless quark form factor $\gamma^* \to q\bar q$ and gluon form factor $H\to gg$ to all orders in the dimensional regularisation parameter $\epsilon=(4-d)/2$. The two-loop contributions to the…
We obtain a closed form effective potential at the one-loop level of a Two Higgs Doublet Model. Through the loop expansion we reproduce the expression presented by Weinberg and Coleman, showing explicitly every step involved in the…