Related papers: Large forward-backward asymmetry in B --> K mu+ mu…
We study an SU(3)^2 axigluon model introduced by Frampton, Shu, and Wang to explain the recent Fermilab Tevatron observation of a significant positive enhancement in the top quark forward-backward asymmetry relative to standard model…
The angular distribution of $B\to K\bar\ell\ell$ ($\ell = e,\,\mu,\,\tau$) depends on two parameters, the lepton forward-backward asymmetry, $A_{\rm FB}^\ell$, and the flat term, $F_H^\ell$. Both are strongly suppressed in the standard…
The anomalies in the measurements of observables involving $b \to s \mu\mu$ decays, namely $R_K$, $R_{K^*}$, $P_5^{\prime}$, and $B_s^\phi$, may be addressed by adding lepton-universality-violating new physics contributions to the effective…
In this letter, we consider the constraints imposed by the recent measurement of B_s - bar B_s mixing on the new physics contribution to the rare decay B_s --> mu+ mu-. New physics in the form vector and axial-vector couplings is already…
We study possible New Physics (NP) effects in the exclusive decays $\bar{B}^0 \to D^{(\ast)} \tau^- \bar{\nu}_{\tau}$. We extend the Standard Model (SM) by taking into account right-handed vector (axial), left- and right-handed…
Using the most general effective Hamiltonian comprising scalar,vector and tensor type interactions, we have written the branching ratio, the forward-backward (FB) asymmetry and the normalized FB asymmetry as functions of the new Wilson…
Forward-backward asymmetry $A_{\rm FB}$ is an essential observable to study the nature of coupling in the standard model and physics beyond the standard model, as shown at LEP and Tevatron. As a proton-proton collider, the LHC does not have…
I show that there are eight new physics operators that contribute to top pair production and subsequent decay in interference with the leading SM process at the Tevatron and estimate their expected statistical inaccuracies. All fully…
We consider a flavour conserving two Higgs doublet model that consists of a type I (or X) quark sector and a generalized lepton sector where the Yukawa couplings of the charged leptons to the new scalars are not proportional to the lepton…
We study the decay B -> K* l+ l- in the QCD factorization approach and propose a new integrated observable whose dependence on the form factors is almost negligible, consequently the non--perturbative error is significantly reduced and…
We analyze the possibility to accommodate current $b \to s \ell^+ \ell^-$ anomalies with TeV-scale mediators that couple to right-handed top quarks and muons, contributing to $b \to s \ell^+ \ell^-\,$ at the one-loop level. We use the…
Composite bosons, here called {\it quasibosons} (e.g. mesons, excitons, etc.), occur in various physical situations. Quasibosons differ from bosons or fermions as their creation and annihilation operators obey non-standard commutation…
The form factors for the hadron matrix element of the QCD energy-momentum tensor not only describe the coupling of the hadron with a graviton as the ``gravitational form factors'', but also serve as unique quantities for describing the…
The status of the Unitarity Triangle beyond the Standard Model including the most recent results on Delta m_s, on dilepton asymmetries and on width differences is presented. Even allowing for general New Physics loop contributions the…
We consider the most general new physics effective Lagrangian for b--> s l+ l-. We derive the upper limit on the branching ratio for the processes B_s--> l^+ l- where l=e, mu, subject to the current experimental bounds on related processes,…
Recent results from LHCb have confirmed the long-standing $P_5^\prime$ anomaly, an intriguing discrepancy in the angular distribution of the $B \to K^* \mu^+\mu^-$ decay that might be a sign of new physics. In addition, the new results hint…
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,…
A novel functorial relationship in perturbative quantum field theory is pointed out that associates Feynman diagrams (FD) having no external line in one theory ${\bf Th}_1$ with singlet operators in another one ${\bf Th}_2$ having an…
We determine the dominant missing Standard Model (SM) contribution to the top quark pair forward-backward asymmetry at the Tevatron. Contrary to past expectations, we find a large, around 27%, shift relative to the well-known value of the…
The azimuthal asymmetry and the transverse momentum of forward produced charged hadrons in deep inelastic muon scattering have been studied as a function of the event kinematics and of the hadron variables. Primordial $k_T$ of the struck…