Search results for "Yukawa [coupling]"
showing 10 items of 110 documents
Phenomenology of enhanced light quark Yukawa couplings and the W±h charge asymmetry
2017
I propose the measurement of the $W^\pm h$ charge asymmetry as a consistency test for the Standard Model (SM) Higgs, which is sensitive to enhanced Yukawa couplings of the first and second generation quarks. I present a collider analysis for the charge asymmetry in the same-sign lepton final state, $p p \to W^\pm h \to (\ell^\pm \nu) (\ell^\pm \nu jj)$, aimed at discovery significance for the SM $W^\pm h$ production mode in each charge channel with 300 fb$^{-1}$ of 14 TeV LHC data. Using this decay mode, I estimate the statistical precision on the charge asymmetry should reach 0.4\% with 3 ab$^{-1}$ luminosity, enabling a strong consistency test of the SM Higgs hypothesis. I also discuss di…
Scattering of Particles by Potentials
2013
The three prototypes of spectra of self-adjoint operators, the discrete spectrum, with or without degeneracy, the continuous spectrum, and the mixed spectrum, as well as the corresponding wave functions, contain important information about the physical systems that they describe
Towards the field theory of the Standard Model on fractional D6-branes on T6 /ℤ6 ′ : Yukawa couplings and masses
2012
We present the perturbative Yukawa couplings of the Standard Model on fractional intersecting D6-branes on T6/Z6' and discuss two mechanisms of creating mass terms for the vector-like particles in the matter spectrum, through perturbative three-point couplings and through continuous D6-brane displacements.
Amorphous silica modeled with truncated and screened Coulomb interactions: A molecular dynamics simulation study
2007
We show that finite-range alternatives to the standard long-range BKS pair potential for silica might be used in molecular dynamics simulations. We study two such models that can be efficiently simulated since no Ewald summation is required. We first consider the Wolf method, where the Coulomb interactions are truncated at a cutoff distance r_c such that the requirement of charge neutrality holds. Various static and dynamic quantities are computed and compared to results from simulations using Ewald summations. We find very good agreement for r_c ~ 10 Angstroms. For lower values of r_c, the long--range structure is affected which is accompanied by a slight acceleration of dynamic properties…
The build-up and relaxation of stresses in a glass-forming soft-sphere mixture under shear: A computer simulation study
2009
Molecular-dynamics computer simulations in conjunction with Lees-Edwards boundary conditions are used to investigate a glass-forming binary Yukawa fluid under shear. The transition from the elastic response to plastic flow is elucidated by studying the stress relaxation after switching off the shear. We find a slow stress relaxation starting from states in the elastic regime and a fast one starting from states in the plastic-flow regime. We show that these relaxation patterns are related to a different distribution of local microscopic stresses in both cases.
Screening effects in Relativistic Models of Dense Matter at Finite Temperature
1998
We investigate screening effects of the medium on the potential interaction between two static 'charges' for different models of dense plasmas in the one-boson exchange approximation. The potential can exhibit an oscillatory behavior, which is related to the analytic structure of the corresponding boson propagators in the complex $q$-plane. We have first revisited the one-pion exchange in a nuclear medium. In addition to Friedel oscillations, which are associated to branch cuts in the $q$-plane, there appears another oscillatory component, which arises from a pole on the pion propagator. This pole is located appart from the axes, giving rise to an oscillating Yukawa-like potential. Therefor…
The importance of being rigid: D6-brane model building on with discrete torsion
2013
Model building with rigid D6-branes on the Type IIA orientifold onT 6 =Z2 Z 0 with discrete torsion is considered. The systematic search for models of particle physics is signicantly reduced by proving new symmetries among dierent lattice orientations. Suitable rigid D6-branes without matter in adjoint and symmetric representations are classied, and SO(2N) and USp(2N) gauge factors on orientifold invariant D6-branes are distinguished in terms of their discrete Wilson line and displacement parameters. Constraints on the nonexistence of exotic matter prohibit global completions of local MSSM and leftright symmetric models, while globally dened supersymmetric Pati-Salam models are found. For t…
Exclusive radiative Higgs decays as probes of light-quark Yukawa couplings
2015
We present a detailed analysis of the rare exclusive Higgs-boson decays into a single vector meson and a photon and investigate the possibility of using these processes to probe the light-quark Yukawa couplings. We work with an effective Lagrangian with modified Higgs couplings to account for possible new-physics effects in a model-independent way. The h->V\gamma{} decay rate is governed by the destructive interference of two amplitudes, one of which involves the Higgs coupling to the quark anti-quark pair inside the vector meson. We derive this amplitude at next-to-leading order in \alpha_s using QCD factorization, including the resummation of large logarithmic corrections and accounting f…
Flavour Conservation in Two Higgs Doublet Models
2018
In extensions of the Standard Model with two Higgs doublets, flavour changing Yukawa couplings of the neutral scalars may be present at tree level. In this work we consider the most general scenario in which those flavour changing couplings are absent. We re-analyse the conditions that the Yukawa coupling matrices must obey for such \emph{general flavour conservation} (gFC), and study the one loop renormalisation group evolution of such conditions in both the quark and lepton sectors. We show that gFC in the leptonic sector is one loop stable under the Renormalization Group Evolution (RGE) and in the quark sector we present some new Cabibbo like solution also one loop RGE stable. At a pheno…
Flavor Symmetry and Vacuum Aligned Mass Textures
2006
21 pages, 2 figures.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-ph/0609220