相关论文: Chirality structure of vector like new physics ope…
In the testable Flipped $SU(5)\times U(1)_X$ model with TeV-scale vector-like particles from F-theory model building dubbed as the flip SU(5) model, we study the vector-like quark contributions to B physics processes, including the quark…
In many extensions of the Standard Model flavour changing neutral current processes can be mediated by tree-level heavy neutral scalars and/or pseudo-scalars H^0(A^0). This generally introduces new sources of flavour violation and CP…
Recently, the experimental measurements of the branching ratios and different polarization asymmetries for the processes occurring through flavor-changing-charged current $b\rightarrow c\tau\overline{\nu}_{\tau}$ transitions by BABAR,…
We discuss the phenomenology of right-handed charged currents in the framework of the Standard Model Effective Field Theory, in which they arise due to a single gauge-invariant dimension-six operator. We study the manifestations of the nine…
Recent lattice QCD calculations of direct CP violation in $K_L \to \pi \pi$ decays indicate tension with the experimental results. Assuming this tension to be real, we investigate a possible beyond-the-Standard Model explanation via…
Model independent phenomenological studies, ranging from neutrino to B-physics, often consider effective interactions involving either purely vector (V), purely axial vector (A), or mixed vector and axial vector (V, A) couplings. While pure…
We study the decays $B\to D^{(\ast)}\tau\nu_{\tau}$ in light of the available data from BABAR, Belle and LHCb. We divide our analysis into two parts: in one part we fit the form-factors in these decays directly from the data without adding…
The leading vector coupling defined in the semileptonic decay of a baryon is revisited in the framework of large-$N_c$ baryon chiral perturbation. Aspects of $SU(3)$ flavor symmetry breaking are taken into account in two ways: Explicitly…
The persistent anomalies observed in $B$ mesons related to $b \to s \mu^+ \mu^-$ transitions point to the potential for new physics beyond the Standard Model. To explore this further, we conduct an analysis of the exclusive semileptonic…
Recent experimental results on exclusive semi-tauonic B meson decays, B -> D(*) tau nu, showing sizable deviations from the standard model prediction, suggest a new physics in which the structure of the relevant weak charged interaction may…
The effective theory based on combined chiral and heavy quark symmetry, the heavy meson chiral perturbation theory, is applied to studying the role of resonances in various processes of heavy mesons within and beyond the Standard Model.…
In this article, we perform a sensitivity study of an unbinned angular analysis of the $B\to D^*\ell \nu_\ell$ decay, including the contributions from the right-handed current. We show that the angular observable can constrain very strongly…
Transverse asymmetries in the decay B->K*(K pi)l+l- are an extremely sensitive probe of right-handed flavour-changing neutral currents. We show how to include the contribution from the chiral partner of the electromagnetic operator on the…
We study the $B$ meson radiative decay $B \to X_s \gamma$ in the vector quark model. Deviation from the Standard Model arises from the non-unitarity of the charged current KM matrix and related new FCNC interactions. We establish the…
We examine in detail the semi-leptonic decay $\Lambda_b \to \Lambda_c \tau{\bar \nu}_{\tau}$, which may confirm previous hints, from the analogous $B$ decay, of a new physics beyond the standard model. First of all, starting from rather…
Recent lattice determinations of direct CP violation in kaon decays, parametrized by $\epsilon'$, suggest a discrepancy of several sigma between experiment and the standard model. Assuming that this situation is due to new physics, we…
We study the decay $K_L -> e\mu$ in minimal extensions of the Standard Model based on the gauge groups $SU(2)_L x U(1)_Y$ and $SU(2)_R x SU(2)_L x U(1)_{B-L}$, in which heavy Majorana neutrinos are present. In $SU(2)_L x U(1)_Y$ models with…
In this work, we have conducted a comprehensive and systematic theoretical investigation of the full cascade decays of charged pseudoscalar mesons, specifically $D_s$, $D$, $B$, and $B_c$, into $\tau \nu_\tau$, followed by the subsequent…
We investigate the influence of the fourth generation quarks on the branching ratio and the CP-asymmetry in B -->\pi \ell^+ \ell^- decay. Taking the |V_{t'd}V_{t'b}| ~ 0.001 with phase about 10 degree, which is consistent with the…
We study the lepton angular distributions in $B\to D^{(*)} \ell \nu_{\ell}$ decays. The lepton angular asymmetries in the decays with the general effective interactions are examined. We demonstrate that the asymmetries are sensitive to new…