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Otto C. W. Kong

Publications and source records attributed to Otto C. W. Kong.

At least 55 records · Page 3Linked to original sources

The Quantum World is an AdS_5 with the Quantum Relativity Symmetry SO(2,4)

Quantum relativity as a generalized, or rather deformed, version of Einstein relativity with a linear realization on a classical six-geometry beyond the familiar setting of space-time offer a new framework to think about the quantum space-time structure. The formulation requires two deformations to be implemented through imposing two fundamental invariants. We take them to be the independent Planck mass and Planck length. Together, they gives the quantum $\hbar$. The scheme leads to {\small \boldmath\protect SO(2,4)} as the relativity symmetry. The quantum world has an AdS$_5$ `classical' geometry, which is parallel to the "conformal universe", but not scale invariant.

gr-qc↗

Quark Loop Contributions to Neutron, Deuteron, and Mercury EDMs from Supersymmetry without R parity

We present a detailed analysis of the neutron, deuteron and mercury electric dipole moment from supersymmetry without R parity, focusing on the quark-scalar loop contributions. Being proportional to top Yukawa and top mass, such contributions are often large. Analytical expressions illustrating the explicit role of the R-parity violating parameters are given following perturbative diagonalization of mass-squared matrices for the scalars. Dominant contributions come from the combinations $B_i λ^{\prime}_{ij1}$ for which we obtain robust bounds. It turns out that neutron and deuteron EDMs receive much stronger contributions than mercury EDM and any null result at the future deuteron EDM experiment or Los Alamos neutron EDM experiment can lead to extra-ordinary constraints on RPV parameter space. Even if R-parity violating couplings are real, CKM phase does induce RPV contribution and for some cases such a contribution is as strong as contribution from phases in the R-parity violating couplings.Hence, we have bounds directly on $|B_i λ^{\prime}_{ij1}|$ even if the RPV parameters are all real. Interestingly, even if slepton mass and/or $μ_0$ is as high as 1 TeV, it still leads to neutron EDM that is an order of magnitude larger than the sensitivity at Los Alamos experiment. Since the results are not much sensitive to $\tan β$, our constraints will survive even if other observables tighten the constraints on $\tan β$.

hep-ph↗

Flavor Changing Higgs Decays in Supersymmetry with Minimal Flavor Violation

We study the flavor changing neutral current decays of the MSSM Higgs bosons into strange and bottom quarks. We focus on a scenario of minimum flavor violation here, namely only that induced by the CKM matrix. Taking into account constraint from $b\to s γ$, $δρ$ as well as experimental constraints on the MSSM spectrum, we show that the branching ratio of $(Φ\to b\bar{s})$ and $(Φ\to \bar{b}s)$ combined, for $Φ$ being either one of the CP even Higgs states, can reach the order $10^{-4}$-$10^{-3}$ for large $\tanβ$, large $μ$, and large $A_t$. The result illustrates the significance of minimal flavor violation scenario which can induce competitive branching fraction for flavor changing Higgs decays. This can be compared with the previous studies where similar branching fraction has been reported, but with additional sources of flavor violations in squark mass matrices. We also discuss some basic features of the flavor violating decays in the generic case.

hep-ph↗

Physics of Quantum Relativity through a Linear Realization

The idea of quantum relativity as a generalized, or rather deformed, version of Einstein (special) relativity has been taking shape in recent years. Following the perspective of deformations, while staying within the framework of Lie algebra, we implement explicitly a simple linear realization of the relativity symmetry, and explore systematically the resulting physical interpretations. Some suggestions we make may sound radical, but are arguably natural within the context of our formulation. Our work may provide a new perspective on the subject matter, complementary to the previous approach(es), and may lead to a better understanding of the physics.

gr-qc↗

Quark Loop Contribution to Neutron EDM from R-parity Violation

We present a detailed analysis together with numerical calculations on one-loop contributions to the neutron electric dipole moment from supersymmetry without R parity, focusing on the quark-scalar loop contributions. Complete formulas are given for the various contributions through the quark dipole operators. Analytical expressions illustrating the explicit role of the R-parity violating parameters are given following perturbative diagonalization of mass-squared matrices for the scalars. Dominant contributions come from the combinations $B_i^{\ast} λ^{\prime}_{ij1}$ for which we obtain robust bounds. Even if the R-parity violating couplings are real, CKM phase does induce RPV contribution and for some cases such a contribution is as strong as contribution from phases in the R-parity violating couplings. Hence, we have bounds directly on $|B_i^{\ast} ł^{\prime}_{ij1}|$ even if the parameters are all real.

hep-ph↗

B--> X_s + gamma in Supersymmetry without R-parity

We present a systematic analysis of the decay B--> X_s + gamma at the leading log within the framework of Supersymmetry without R-parity. We point out some new contributions in the form of bilinear-trilinear combination of R-parity violating (RPV) couplings that are enhanced by large tanbeta. We also improve by a few orders of magnitude, bounds on several combinations of R-parity violating parameters.

hep-ph↗

Radiative B decays in Supersymmetry without R-parity

We present a systematic analysis of all the contributions at the leading log order to the branching ratio of the inclusive radiative B decay, B --> X_s + gamma in the framework of supersymmetry without R-parity. The relevant set of four-quark operators involved in QCD running are extended from 6 (within SM and MSSM) to 24, with also many new contributions to the Wilson coefficients of (chromo)magnetic penguins for either chiral structure. We present complete analytical results here without any a priori assumptions on the form of R-parity violation. Mass eigenstate expressions are given, hence the results are free from the commonly adopted mass-insertion approximation. In the numerical analysis, we focus here only on the influence of the trilinear lambda-prime couplings and report on the possibility of a few orders of magnitude improvement for the bounds on a few combinations of the lambda-prime couplings. Our study shows that the Wilson coefficients of the current-current operators due to R-parity violation dominate over the direct contributions to the penguins. However, the inter-play of various contributions is complicated due to the QCD corrections which we elaborate here.

hep-ph↗

tanbeta enhanced contributions to b--> s gamma in SUSY without R-parity

We present a systematic analysis of the decay b --> s gamma at the leading log within the framework of Supersymmetry without R-parity. We point out some new contributions in the form of bilinear-trilinear combination of R-parity violating (RPV) couplings that are enhanced by large tanbeta. We also improve by a few orders of magnitude, bounds on several combinations of RPV parameters.

hep-ph↗

Little Higgs Model Completed with a Chiral Fermionic Sector

The implementation of the little Higgs mechanism to solve the hierarchy problem provides an interesting guiding principle to build particle physics models beyond the electroweak scale. Most model building works, however, pay not much attention to the fermionic sector. Through a case example, we illustrate how a complete and consistent fermionic sector of the TeV effective field theory may actually be largely dictated by the gauge structure of the model. The completed fermionic sector has specific flavor physics structure, and many phenomenological constraints on the model can thus be obtained beyond gauge, Higgs, and top physics. We take a first look on some of the quark sector constraints.

hep-ph↗

Some Novel Contributions to Radiative B Decay in Supersymmetry without R-parity

We present a systematic analysis at the leading log order of the influence of combination of bilinear and trilinear R-parity violating couplings on the decay b-->s gamma. Such contributions have never been explored in the context of this decay. We show that influence of charged-slepton-Higgs mixing mediated loops can dominate the SM and MSSM contributions and hence can provide strong bounds on the combination of bilinear-trilinear R-parity violating couplings. Such contributions are also enhanced by large tan beta. With substantially extended basis of operators (28 operators), we provide illustrative analytical formulae of the major contributions to complement our complete numerical results which demonstrate the importance of QCD running effects.

hep-ph↗

On Extended Electroweak Symmetries

We discuss extensions of the Standard Model through extending the electroweak gauge symmetry. An extended electroweak symmetry requires a list of extra fermionic and scalar states. The former is necessary to maintain cancellation of gauge anomalies, and largely fixed by the symmetry embedding itself. The latter is usually considered quite arbitrary, so long as a vacuum structure admitting the symmetry breaking is allowed. Anomaly cancellation may be used to link the three families of quarks and leptons together, given a perspective on flavor physics. It is illustrated lately that the kind of models may also have the so-called little Higgs mechanism incorporated. This more or less fixes the scalar sector and take care of the hierarchy problem, making such models of extended electroweak symmetries quite appealing candidates as TeV scale effective field theories.

hep-ph↗

On the Formulation of the Generic Supersymmetric Standard Model (or Supersymmetry without R parity)

The generic supersymmetric version of the Standard Model would have the minimal list of superfields incorporating the Standard Model particles, and a Lagrangian dictated by the Standard Model gauge symmetries. To be phenomenologically viable, soft supersymmetry breaking terms have to be included. In the most popular version of the supersymmetric Standard Model, an {\it ad hoc} discrete symmetry, called R parity, is added in by hand. While there has been a lot of various kinds of R-parity violation studies in the literature, the complete version of supersymmetry without R parity is not popularly appreciated. In this article, we present a pedagogical review of the formulation of this generic supersymmetric Standard Model and give a detailed discussion on the basic conceptual issues involved. Unfortunately, there are quite some confusing, or even plainly wrong, statements on the issues within the literature of R-parity violations. We aim at clarifying these issues here. We will first discuss our formulation, about which readers are urged to read without bias from previous acquired perspectives on the topic. Based on the formulation, we will then address the various issues . In relation to phenomenology, our review here will not go beyond tree-level mass matrices. But we will give a careful discussion of mass matrices of all the matter fields involved. Useful expressions for perturbative diagonalizations of the mass matrices at the phenomenologically interesting limit of corresponds to small neutrino masses are derived. All these expressions are given in the fully generic setting, with information on complex phases of parameters retained. Such expressions have been shown to be useful in the analyses of various phenomenological features.

hep-ph↗

Higgs sector contributions to Δa_μand the constraints on two-Higgs-doublet-model with and without SUSY

Interesting contributions to $Δa_μ$ from a two-Higgs-doublet-model is coming from a two-loop Barr-Zee diagram for most part of the parameter space -- a fact that has been overlooked by some Higgs/SUSY experts. A definite positive contribution has requirements that go against precision EW data and other known constraints. For the case without SUSY, in particular, this is almost enough to kill the two-Higgs-doublet-model (II). We will discuss the interplay of all the constraints and their implications.

hep-ph↗

Flavor and Little Higgs

We discuss the proper starting point to look into flavor physics under the perspective of solving the hierarchy problem with the little Higgs mechanism -- the construction of anomaly free fermionic spectra of the effective theory of extended electroweak gauge symmetry around the TeV scale. Anomaly cancellations among the three SM families, plus extra fermions, are typically needed, giving family non-universal flavor structures. Such a completed and consistent fermionic spectrum supplements a scalar sector little Higgs model, turning the latter into a realistic model the phenomenological viability of which can then be investigated. The implications for flavor physics are specially interesting. We give more elaborated discussion here on our basic perspective, trying to clarify on issues that are in our opinion under-appreciated. We also add a brief comment of little Higgs versus supersymmetry.

hep-ph↗

Anomaly Free Gauged $SU(4)_L\times U(1)_X$ Models with Little Higgs

We present an analysis showing how anomaly free fermionic spectra with consistent embeddings of the Standard Model spectrum under $SU(3)_C\times SU(2)_L\times U(1)_Y \subset SU(3)_C\times SU(N)_L\times U(1)_X$ for any $N>2$ can be obtained, with special focus on the $N=3 {and} 4$ cases. The construction is motivated by the little Higgs mechanism. We discuss the relevancy of the fermionic spectra to the latter, concentrating on two N=4 models, without fermions of exotic charges. Such models hold the promise to address and solve all the major theoretical as well as phenomenological problems of the Standard Model at the TeV scale.

hep-ph↗

A Detailed Analysis of One-loop Neutrino Masses from the Generic Supersymmetric Standard Model

In the generic supersymmetric standard model which had no global symmetry enforced by hand, lepton number violation is a natural consequence. Supersymmetry, hence, can be considered the source of experimentally demanded beyond standard model properties for the neutrinos. With an efficient formulation of the model, we perform a comprehensive detailed analysis of all one-loop contributions to neutrino masses.

hep-ph↗

Neutrino Masses and Beyond from Supersymmetry

A generic form of the supersymmetric SM naturally gives rise to the lepton number violating neutrino masses and mixings, without the need for extra superfields beyond the minimal spectrum. Hence, SUSY can be consider the origin of beyond SM properties of neutrinos. We have developed a formulation under which one can efficiently analyze the model. Various sources of neutrino masses are discussed in details. Such mass contributions come from lepton number and flavor violating couplings that also give rise to a rich phenomenology of the neutrinos and other leptons, to be discussed.

hep-ph↗

Can the Two-Higgs-Doublet Model Survive the Constraint from the Muon Anomalous Magnetic Moment as Suggested?

Requiring the two-Higgs-doublet model II to accommodate the 3$σ$ deviation in the muon anomalous magnetic moment imposes specific constraints on the Higgs spectrum. We analyze the combination of all the relevant, available, constraints on the model parameter space. The use of constraints from $b\to s γ$, the precision electroweak measurements of $R_b$, and the $ρ$ parameter, together with exclusions from direct searches at LEP, give extremely severe restrictions on the model parameters. That is "almost enough" to kill the model altogether. The exclusion would be even stronger if the direct searches can be optimized to complement the other constraints, as will be discussed in details in this work.

hep-ph↗