Related papers: 2-, 3- and 4-Body Decays in the Constructive Stand…
We present a complete set of 4-point amplitudes in the constructive Standard Model at tree level. Any 4-point amplitude can be obtained from the results presented here by a suitable choice of masses, a permutation of the particles (by…
The Feynman diagram generator FeynArts and the computer algebra program FormCalc allow for an automatic computation of 2->2 and 2->3 scattering processes in High Energy Physics. We have extended this package by four new kinematical routines…
The physical process of Higgs decaying to two photons is the most important mode in the discovery of the Higgs particle. Theoretical calculation of $H\rightarrow\gamma\gamma$ amplitude therefore provides us with an avenue to explore the…
The imaginary part of the Feynman amplitude of the $W$-loop contribution to the Higgs decay into two gammas (viewed as a function of the square of the off shell Higgs momentum) is finite and unambiguous. It is presented as the product of an…
In the case of minimal supersymmetric extension of the Standard Model (MSSM), when the pseudoscalar Higgs boson mass is less than the supersymmetry energy scale, the effective theory at the electroweak scale is a two-Higgs-doublet model. We…
Using the classical recursion relations we compute scattering amplitudes in a spontaneously broken Gauge-Higgs theory into final states involving high multiplicities of massive vector bosons and Higgs bosons. These amplitudes are computed…
We derive an effective dimensionally reduced theory for the Standard Model augmented by a real singlet scalar. We treat the singlet as a superheavy field and integrate it out, leaving an effective theory involving only the Higgs and…
We summarize the dominant decay modes of the neutral and charged Higgs bosons in the Minimal Supersymmetric extension of the Standard Model. While two--body decays are in general dominating, the branching ratios for three--body decays of…
In this work, we review and clarify computational issues about the W-gauge boson one-loop contribution to the H -> gamma gamma decay amplitude, in the unitary gauge and in the Standard Model. We find that highly divergent integrals depend…
After discovery of the Higgs boson at CERN the Standard Model acquired a status of the theory of the elementary particles in the electroweak range (up to about 300 GeV). What general conclusions can be inferred from the Standard Model? It…
A complete calculation of the rare three-body decay t --> c h gamma is presented in the framework of the standard model. In the unitary gauge, such a calculation involves about 20 Feynman diagrams. We also calculate this decay in the…
I discuss the decay modes of the neutral and charged Higgs bosons in the minimal supersymmetric extension of the Standard Model. Special emphasis will be put on the the QCD corrections to the hadronic decay modes, the below threshold -three…
Two compact universal extra dimensional models are an interesting class of models for different theoretical and phenomenological issues, such as the justification of having three standard model fermion families, suppression of proton decay…
The constructive method of determining amplitudes from on-shell pole structure has been shown to be promising for calculating amplitudes in a more efficient way. However, challenges have been encountered when a massless internal photon is…
A Standard Model extension with two Majorana neutrinos can explain the measured neutrino masses and mixings, and also account for the matter-antimatter asymmetry in a region of parameter space that could be testable in future experiments.…
The amplitude for Higgs decay to two photons is calculated in renormalizable and unitary gauges using dimensional regularization at intermediate steps. The result is finite, gauge independent, and in agreement with previously published…
As a first step in the aim of arriving at a differential description of neutral Higgs boson decays into heavy quarks, $h \to Q {\bar Q}X$, to second order in the QCD coupling $\alpha_S$, we have computed the $hQ{\bar Q}$ amplitude at the…
State-of-the-art predictions for the Higgs-boson production cross section via gluon fusion and for all relevant Higgs-boson decay channels are presented in the presence of a fourth Standard-Model-like fermion generation. The qualitative…
We provide succinct covariant amplitude decompositions of 2-body weak hadronic decays, with which to compare data, including exclusive rates, helicity amplitudes and polarizations. For weak decays, the systematic dependence of these…
We show how the use of a see-saw mechanism based on a $3 \times 3$ neutrino mass matrix texture can considerably simplify Higgs sectors for quark-lepton symmetric models (and for Standard Model extensions generally). The main theory we…