Related papers: Oblique corrections from triplet quarks
Recent improvements to OPUCEM, the tool for calculation of the contributions of various models to oblique parameters, are presented. OPUCEM is used to calculate the available parameter space for the four family Standard Model given the…
Within the context of the Standard Model, quarks are placed in a $(\mathbf{3},\mathbf{2})\oplus (\mathbf{3},\bar{\mathbf{2}})$ matter field representation of $U_{EW}(2)$. Although the quarks carry unit intrinsic electric charge in this…
We compute the six oblique parameters $S, T, U, V, W, X$ in a New Physics Model with an arbitrary number of new fermions, in arbitrary representations of $SU(2) \times U(1)$, and mixing arbitrarily among themselves. We show that $S$ and $U$…
General formulas as well as leading asymptotics for corrections to Z- and W-boson parameters are derived. Experimental data fits in Standard Model and its extensions are discussed and results are presented.
We investigated the electroweak corrections from one-loop diagrams involving the third generation (s)quarks to the decay width of process $\tilde{\chi}_1^+ \to W^+ \tilde{\chi}_1^{0}$ in the framework of the Minimal Supersymmetric Standard…
Within the standard electroweak model we point out that the $3\times 3$ matrix of quark mixing is characterized by three universal (rephasing-invariant) quantities: one of them for $CP$ violation and the other two for off-diagonal…
The tensor charges of the nucleon are calculated in the framework of the SU(3) chiral quark soliton model. The rotational $1/N_c$ and strange quark mass corrections are taken into account up to linear order. We obtain the following…
The status of the present precision measurements of electroweak observables is reviewed with specific reference to the radiative parameters $S,T,U$ or equivalently $\epsilon_1,\epsilon_2,\epsilon_3$. The significance of the obliqueness…
The standard model accommodates, but does not explain, three families of leptons and quarks, while various extensions suggest extra matter families. The oblique corrections from extra chiral families with relatively light (weak-scale)…
We present a model and process independent study of the contributions from non-Standard Model physics to the oblique parameters S, T and U. We show that within an effective lagrangian parameterization the expressions for the oblique…
We have calculated the one-loop electroweak corrections to the decay t-> bW+, including the counterterm for the CKM matrix elements V(tb). Previous calculations used an incorrect delta V(tb) that led to a gauge dependent amplitude. However,…
We calculate the tree-level oblique corrections to electroweak precision observables generated in higgless models of electroweak symmetry breaking with a 5D SU(2)_L x SU(2)_R x U(1)_{B-L} gauge group on a warped background. In the absence…
The standard electroweak model with Dirac neutrinos is extended by way of the principles of electroweak quark-lepton symmetry and weak topological-charge confinement to account for quark-lepton charge relations which, if not accidental, are…
We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process $H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from the virtual…
We derive QED radiators for the universal corrections to polarized electron scattering. To 5th order in the coupling constant the flavor non-singlet and singlet contributions are calculated. We derive the non-singlet and singlet…
Explicit expressions are derived for the oblique parameters $S$ and $T$ in certain extensions of the standard model. In particular, we consider leptoquarks and bileptons, and find phenomenological constraints on their allowed masses.…
The cross-section for $\gamma\gamma\to t \bar t$ with arbitrary polarized photons is calculated within the electroweak Standard Model including the complete virtual and soft-photonic $O(\alpha)$ corrections. We present a detailed numerical…
The experimental values of $R_b$ and $R_c$ are the only data which do not seem to agree with Standard Model predictions. Although it is still premature to draw any definite conclusions, it is timely to look for new physics which could…
We present a new model based on the SU(3)xSU(2)xU(1) symmetry, in which there is a new consistent set of chiral fermion fields that renders the model free from anomalies. The new fermions do not share the usual family structure of the…
A complication in the treatment of any strongly charged particle is the SU(3) color structure. For the standard model quarks antiquarks and gluons there are various well-known strategies for dealing with the color structure, including…