相关论文: Top A_{FB} and charge asymmetry in flavor-dependen…
Forward-backward asymmetries $A_{FB}^t$ and $A_{FB}^\ell$ are observed in the top quark $t$ rapidity distribution and in the rapidity distribution of charged leptons $\ell$ from top quark decay at the Tevatron proton-antiproton collider,…
We study the impact of an additional $U(1)'$ gauge symmetry with flavour-dependent charges for quarks and leptons on the LHC flavour anomalies observed in $B \to K^* \mu^+\mu^-$, $R(K) = B \to K \mu^+\mu^-/B \to K e^+e^-$, and $h \to…
We construct a novel flavor-dependent gauged lepton number $U(1)_\ell$ model for the hierarchical charged lepton masses and the observed $(g-2)_{e,\mu}$. Only tau participates in the tree-level Standard Model ( SM ) Yukawa interaction. At…
We propose two new observables to measure the charge asymmetry in hadronic top-quark pair production in association with a hard jet. The incline asymmetry, based on the inclination between the planes of initial- and final-state momenta,…
An extension of the Standard Model with anomaly free $U(1)_F$ flavor symmetry is studied in this paper. With this extension and the addition of the right-handed neutrino states, the solution of anomaly free charge assignments is found,…
We show that the recently measured 3.2 $\sigma$ deviations of the charge asymmetry of like-sign dimuon events from the standard model prediction by the D0 collaboration at Tevatron can be explained by introducing the anomalous right-handed…
A non anomalous horizontal $U(1)_H$ gauge symmetry can be responsible for the fermion mass hierarchies of the minimal supersymmetric standard model. Imposing the consistency conditions for the absence of gauge anomalies yields the following…
With the aim of linking natural supersymmetry to flavour physics, a model is proposed based on a family symmetry G \times U(1), where G is a discrete nonabelian subgroup of SU(2), with both F-term and (abelian) D-term supersymmetry…
We systematically study model-independent constraints on the three generic charged Higgs couplings to $b$-quarks and up-type quarks. While existing LHC searches have focussed on the $tb$ coupling, we emphasize that the LHC plays a crucial…
At the LHC, top quark pairs are dominantly produced from gluons, making it difficult to measure the top quark forward-backward asymmetry. To improve the asymmetry measurement, we study variables that can distinguish between top quarks…
We consider a Z' model where the Z' boson couples only to up and top quarks. As a simple setup, one can consider a family-dependent $U(1)'$ symmetry, under which only right-handed up-type quarks are charged. After symmetry breaking, the…
$U(1)^\prime$ extensions of the standard model with generation-dependent couplings to quarks and leptons are investigated as an explanation of anomalies in rare $B$-decays, with an emphasis on stability and predictivity up to the Planck…
In extended Higgs models, a discrete symmetry is needed in the quark sector to avoid tree-level flavor-changing neutral currents. However, this is not necessary the case in the lepton sector. We consider a model in which one Higgs couples…
A sizeable difference in the differential production cross section of top- compared to antitop-quark production, denoted charge asymmetry, has been observed at the Tevatron. The experimental results seem to exceed the theory predictions…
We investigate the attempt using flavor violation gauge interaction in the up sector to explain the LHCb recently observed large $\Delta A_{CP}$ ($A_{CP}(D^{0}\to K^{+}K^{-})-A_{CP}(D^{0}\to \pi^{+}\pi^{-})$). We study an Abelian model that…
Motivated by the $b\to s\ell^+\ell^-$ anomalies recently reported by the LHCb collaboration, I present a class of flavored U(1)' gauge extensions of the Standard Model that naturally accommodates them and possesses a rich phenomenology.…
We provide the most up-to-date predictions for the top-quark charge asymmetry A_C at the LHC with a centre-of-mass energy of 8 TeV. Our result is accurate at the NNLO level in the strong interactions and at the complete-NLO level in both…
A novel model of charged leptons is presented, which contains two basics hypotheses. The first hypothesis is that the Yukawa coupling between Higgs field and charged leptons is the weak interaction, the Higgs field is a scalar intermediate…
The top quark forward-backward asymmetry A_{FB}^t measured at the Tevatron is above the Standard Model prediction by more than 2-sigma deviation, which might be a harbinger for new physics. In this work we examine the contribution to…
We study a simple ultraviolet(UV) complete and anomaly free $Z'$ model based on a U$(1)'$ gauge family symmetry without introducing extra fermions beyond the standard model. The U$(1)'$ group is diagonal in the three family space in which…