Electroweak chiral Lagrangian for a hypercharge-universal topcolor model is investigated. We find that the assignments of universal hypercharge improve the results obtained previously from K.Lane's prototype natural TC2 model by allowing a larger Z' mass resulting in a very small T parameter and the S parameter is still around the order of +1
Topcolor and the First Muon Collider (Talk presented at the Workshop on Physics at the First Muon Collider and at the Front End of the Muon Collider, Nov. 1997)
We present a finite-energy electroweak-monopole solution obtained by considering non-linear extensions of the hypercharge sector of the Electroweak Theory, based on logarithmic and exponential versions of electrodynamics. We find constraints for a class of non-linear extensions and also work out an estimate for the monopole mass in this scenario. We finally derive a lower bound for the energy of the monopole and discuss the simpler case of a Dirac magnetic charge.
While it is known that third family hypercharge models can explain the neutral current $B-$anomalies, it was hitherto unclear whether the $Z-Z^\prime$ mixing predicted by such models could simultaneously fit electroweak precision observables. Here, we perform global fits of several third family hypercharge models to a combination of electroweak data and those data pertinent to the neutral current $B-$anomalies. While the Standard Model is in tension with this combined data set with a $p-$value of $.00068$, simple versions of the models (fitting two additional parameters each) provide much impr…
Strongly electroweak phase transition with $U(1)_{L_μ-L_τ}$ gauged non-zero hypercharge triplet
Yonsei University（延世大学）；Gaya College (A constituent unit of Magadh University, Bodh Gaya)（盖亚学院（巴德伽大学波达伽雅下属单位））；SR University（SR大学）；Asia Pacific Center for Theoretical Physics (APCTP) - Headquarters（亚太理论物理中心总部）；Shiv Nadar IoE Deemed to be University（希夫·纳德尔工程学院 deemed 大学）
We study phenomenology of electroweak-interacting fermionic dark matter (DM) with a mass of $\mathcal{O}(100)$ GeV. Constructing the effective Lagrangian that describes the interactions between the Higgs boson and the SU(2)$_L$ isospin multiplet fermion, we evaluate the electric dipole moment (EDM) of electron, the signal strength of Higgs boson decay to two photons and the spin-independent elastic-scattering cross section with proton. As representative cases, we consider the SU(2)$_L$ triplet fermions with zero/nonzero hypercharges and SU(2)$_L$ doublet fermion. It is found that the electron …
We perform numerical simulations of Cold Electroweak Baryogenesis, including for the first time in the Bosonic sector the full electroweak gauge group SU(2)$\times$U(1) and CP-violation. We find that the maximum generated baryon asymmetry is reduced by a factor of three relative to the SU(2)-only model, but that the quench time dependence is very similar. In addition, we compute the magnitude of the helical magnetic fields, and find that it is proportional to the strength of CP-violation and dependent on quench time, but is not proportional to the magnitude of the baryon asymmetry as proposed …
We study the minimal type-III seesaw model in which we extend the SM by adding two $SU(2)_L$ triplet fermions with zero hypercharge to explain the origin of the non-zero neutrino masses. We show that the naturalness conditions and the limits from lepton flavor violating decays provide very stringent bounds on the model parameters along with the constraints from the stability/metastability of the electroweak vacuum. We perform a detailed analysis of the model parameter space including all the constraints for both normal as well as inverted hierarchies of the light neutrino masses. We find that …
Chiral Scalar Fields, Custodial Symmetry in Electroweak SU(2)L X U(1) and the Quantization of the Electric Charge
我研究的标量表示的电弱群的标准模型，这是一个子群的手征群U（N）L × U（N）R与N味，N甚至，特别强调其手征性质和行为的离散对称性P和CP。它们耗尽了手征群的$2N^2$标量自由度和赝标量自由度，对于手征群，SU（2）L x U（1）可重整化的、无反常的规范理论自然产生。它被证明有一个整体的对角SU（2）V对称性的超荷耦合，成为本地的极限时，后者消失的值独立。当作用于本文所研究的特殊表象所涵盖的四维状态空间时，电荷是这种"保管“对称性的三个生成器之一;因此，后者保持不破缺的对称性与电荷的量子化有关。
We study the constraints on the new parameters in the gauge sector of gauged two Higgs doublet model using the electroweak precision test data collected from the Large Electron Positron Collider (LEP) at and off the Z-pole as well as the current Drell-Yan and high-mass dilepton resonance data from the Large Hadron Collider (LHC). Impacts on the new parameters by the projected sensitivities of various electroweak observables at the Circular Electron Positron Collider (CEPC) proposed to be built in China are also discussed. We also clarify why the Stüeckelberg mass $M_Y$ for the hypercharge $U(1…
We report the most general expression for the chiral charges of a $Z'$ gauge boson coming from an $E_6$ unification model, as a function of the electroweak parameters and the charges of the $U(1)$ factors in the chain of subgroups. These charges are valid for an arbitrary Higgs sector and only depend on the branching rules of the $E_6$ fundamental representation and the corresponding rules for the fermionic representations of their subgroups. By assuming $E_6$ unification, the renormalization group equations~(RGE) allow us to calculate the electroweak parameters at low energies for most of the…
