Beyond the standard model

µ −e conversion in a model of electroweak scale right-handed neutrino mass. We perform a detailed analysis of the µ − e conversion within an extended version of the standard model (SM) with mirror symmetry and low energy of the electroweak scale of the type I seesaw neutrino mass generation. After a brief introduction to the model, we derive the µ − e conversing ratio at one-loop approximation, in which the running inside are W gauge boson or singly charged scalars accompanying with neutrinos, and neutral scalars with new leptons.

14p dianmotminh02 03-05-2024 5 2   Download

Part 2 book "Introduction to nuclear and particle physics" includes content: Properties and interactions of elementary particles, symmetries, discrete transformations, neutral kaons, oscillations, and CP violation, formulation of the standard model, standard model and confrontation with data, beyond the standard model.

194p muasambanhan06 03-02-2024 1 0   Download

We study the FCNC problems in 3-4-1-1 model in a way different from the previous work. The sources of FCNC at the tree-level in the 3-4-1-1 model come from both the gauge and scalar sectors. We show that the most stringently bound on the tree-level FCNC interactions comes from the meson oscillations.

12p vispiderman 15-06-2023 4 2   Download

We investigate the branching ratio of the radiative decay b → sγ in the 3-4-1-1 model with arbitrary charge parameters p,q. If the spontaneous breaking of the gauge group symmetry down to the electroweak group is around a few TeVs, the predictions for the branching ratio Br(b → sγ) and meson mixing are consistent with experimental constraints.

12p vispiderman 15-06-2023 5 2   Download

The decays of the Higgs boson H_1→Z_γ are discussed in the simplest 3-3-1 model. Analytic formulas for one-loop contributions were constructed using well-known general results. We will show that new particles predicted by this simplest 3-3-1 model may gice significant effects to this decay of the standard model-like Higgs boson. From numerical investigation, some details and properties of this decay are presented the may be useful for comparing with the experimental results that will be detected in the future.

4p trinhthamhodang11 04-05-2021 10 2   Download

This paper investigate an extension of the standard model with vector-like fermions and an extra Abelian gauge symmetry. The particle mass spectrum is calculated explicitly. The Lagrangian terms for all the gauge interactions of leptons and quarks in the model are derived. Observe that while there is no new mixing in the lepton sector, the quark mixing plays an important role in the magnitudes of gauge interactions for quarks, particularly the interactions with massive W, Z and Z0 bosons.

14p nguyenxuankha_bevandan 14-08-2020 11 1   Download

Lepton flavor violating (LFV) decays of charged leptons µ → eγ and SM-like Higgs boson h → µτ are discussed in the framework of the economical 3-3-1 model adding three additional singlets neutrinos (E331XR).

10p viryucha2711 24-04-2019 21 0   Download

We present full electroweak radiative corrections to ݁e+ e- ZH with the initial beam polarizations at the International Linear Collider (ILC). The calculation is checked numerically by using three consistency tests that are ultraviolet finiteness, infrared finiteness, and gauge parameter independence.

12p danhvi10 22-11-2018 25 1   Download

Lepton flavor violating (cLFV) decays of charged leptons such as τ → µγ, τ → eγ, µ → eγ,..., are now the subjects of experiments as signals of new Physics beyond the Standard Model (SM). In the limit of the unitary gauge, we prove that contributions from one loop corrections to the above decays are very small in the framework of the economical 3-3-1 model.

13p thuyliebe 09-10-2018 32 2   Download

We show that the mass matrix of electrically neutral gauge bosons in the recent proposed model based on SU(3)C ⊗ SU(3)L ⊗ U(1)X group with three neutrino singlets [9] has two exact eigenvalues and corresponding eigenvectors. Hence the neutral non-Hermitian gauge boson X0 µ is properly determined. With extra vacuum expectation values of the Higgs fields, there are mixings among charged gauge bosons W± and Y ± as well as among neutral gauge bosons Z,Z 0 and X0 .

11p thuyliebe 09-10-2018 41 1   Download

Neutrino masses and mixing in an extended standard model acquiring an A4 flavor symmetry are considered. The corresponding three-neutrino mixing matrix obtained via a perturbative method allows us to determine the Dirac CP violation phase (δCP) as a function of the mixing angles (θ12,θ23,θ13). Then, numerical values and distributions of δCP are given. The latter values are quite close to the global fits of the experimental data for both the normal ordering and inverse ordering of the neutrino masses.

10p thuyliebe 08-10-2018 33 1   Download

Over several years, we have developed an approach to spoken dialogue systems that includes rule-based and trainable dialogue managers, spoken language understanding and generation modules, and a comprehensive dialogue system architecture. We present a Reinforcement Learning-based dialogue system that goes beyond standard rule-based models and computes on-line decisions of the best dialogue moves. The key concept of this work is that we bridge the gap between manually written dialog models (e.g.

4p hongphan_1 15-04-2013 72 3   Download

In this paper, with a belief that a language model that embraces a larger context provides better prediction ability, we present two extensions to standard n-gram language models in statistical machine translation: a backward language model that augments the conventional forward language model, and a mutual information trigger model which captures long-distance dependencies that go beyond the scope of standard n-gram language models.

10p hongdo_1 12-04-2013 64 3   Download

Next, a few words about our strategy. It is well recognized now that one has to go beyond the Einstein-Hilbert action for gravity, both from the experimental viewpoint (eg.,because of Dark Energy) and from the theoretical viewpoint (eg., because of the UV incompleteness of quantized Einstein gravity, and the need of its unification with the Standard Model of Elementary Particles). In our approach, the origin of inflation is purely geometrical, ie. is closely related to space-time and gravity.

0p lulaula 25-10-2012 61 8   Download

However, inflation is just the cosomological paradigm, not a theory! The known field-theoretical mechanisms of inflation use a slow-roll scalar field φ (called inflaton) with proper scalar potential V(φ) (12; 13). The scale of inflation is well beyond the electro-weak scale, ie. is well beyond the Standard Model of Elementary Particles! Thus the inflationary stage in the early universe is the most powerful High-Energy Physics (HEP) accelerator in Nature (up to 1010 TeV).

0p lulaula 25-10-2012 34 3   Download