相关论文: The process \gamma \gamma -> \gamma \gamma, \gamma…
We study the helicity amplitudes and the observables of the process $\gamma \gamma \to \gamma Z$ at high energy. As in the case of the $\gamma \gamma \to \gamma\gamma$ process studied before, the relevant diagrams in the standard model (SM)…
We study the helicity amplitudes of the process \gamma \gamma \to \gamma \gamma at high energy, which in the standard and SUSY models first arise at the one-loop order. In the standard model (SM), the diagrams involve W and charged quark…
We study the helicity amplitudes of the process gamma gamma to ZZ in the Standard Model at high energy. These amplitudes receive contributions from the W and charged quark and lepton loops, analogous to those encountered in the gamma gamma…
The process gamma gamma to ZH first arises at the 1-loop level, and as such it provides remarkable tests of the structure of the electroweak Higgs sector. These tests are complementary to those in the gauge sector involving gamma gamma to…
We study the process $e^-e^+\to \gamma H$, where $H$ represents $H_{SM}$, $h^0$ or $H^0$, which occurs at the one loop level in the standard model (SM) or in the minimal supersymmetric standard model (MSSM). We establish supersimple (sim)…
If the Standard Model (SM) Higgs particle is sufficiently heavy, then its contribution to gamma gamma to Z Z should be largely imaginary, interfering with the also predominantly imaginary SM "background" generated by the W-loop. For…
$Z \to \gamma \gamma$ decay amplitude is considered and proven to be zero due to properties of polarization vectors and Bose statistics. Triangular diagrams for a pseudoscalar $\to \gamma \gamma$ and $Z \to \gamma \gamma$ processes with…
The helicity amplitudes for the process $\gamma \gamma \to A^0 A^0$ are studied to 1-loop order in the minimal SUSY (MSSM) model, where $A^0$ is the CP-odd Higgs particle. Simple exact analytic formulae are obtained, in terms of the $C_0$…
$\gamma\gamma\to\gamma Z$ scattering at the Photon Linear Collider is considered. Explicit formulas for helicity amplitudes due to $W$ boson loops are presented. It is shown that the $Z\gamma$ pair production will be easily observable at…
We present the one-loop QCD corrections to the helicity amplitudes for the processes $q\qb \to W^+ W^-, Z Z, W^\pm Z, W^\pm \gamma$, or $Z \gamma$, including the subsequent decay of each massive vector boson into a pair of leptons. We also…
The ATLAS and CMS Collaborations reported that the observed number of Higgs boson decays into a $Z$ boson and a photon is $\mu = 2.2 \pm 0.7$ times higher than predicted by the Standard Model. Initially, this discrepancy was attributed to a…
Two decay channels $h\rightarrow \gamma \gamma, Z\gamma$ of the Standard Model-like Higgs in a left-right symmetry model are investigated under recent experimental data. We will show there exist one-loop contributions that affect the…
The partial Higgs width $\Gamma (H \longrightarrow \gamma \gamma)$ is important at the LHC for Higgs masses in the MSSM mass window up to 140 GeV as a relatively background free signal of a fundamental scalar. At the photon photon mode at…
We study the process $e^-e^+\to ZH$ where $H$ represents the standard model (SM) Higgs particle $H_{SM}$, or the MSSM ones $h^0$ and $H^0$. In each case, we compute the one-loop effects and establish very simple expressions, called…
The general two-higgs doublet model (2HDM) contains a rich spectrum of neutral and charged Higgs bosons, whose detection would be a clear signal of new physics. When the Higgs potential is CP-conserving, the spectrum includes a pseudoscalar…
According to the helicity conservation (HCns) theorem, the sum of the helicities should be conserved, in any 2-to-2 processes in MSSM with R-parity conservation, at high energies; i.e. all amplitudes violating this rule, must vanish…
Neutral diboson processes are precise probes of the Standard Model (SM) of particle physics, which entail high sensitivity to new physics effects. We identify in terms of dimension-8 effective operators the leading departures from the SM…
We have performed a complete one-loop calculation of $\gamma \gamma \rightarrow ZZ$ in the Standard Model, including both gauge bosons and fermions in the loop. We confirm the large irreducible continuum background from the $W$-boson loop…
We investigate the sensitivity of the reaction $\gamma\gamma\to W^+W^-$ to the Higgs sector based on the complete one-loop corrections in the minimal Standard Model and the gauged non-linear $\sigma$-model. While this sensitivity is very…
We study the complete one loop contribution to $H^\pm\to W^\pm Z$ and $H^\pm \to W^\pm \gamma$ in the Minimal Supersymmetric Standard Model (MSSM).