Anomalies in decays induced by b→ct Ve(l=e,μ,T)transitions may imply lepton flavor universality violations,which raises questions on such phenomena in the D decays induced by c→(s,d)t+ve transitions.Current measurements of the pure leptonic and semi-leptonic D decays agree with the standard model(SM)predictions,and such agreements can be used to constrain the new physics(NP)contributions.In this work,we extend SM by as-suming general efective Hamiltonians describing the c→(s,d)t+Ve transitions including the full set of the four-fermion operators.With the latest experimental data,we perform a least χ^(2) fit of the Wilson cofficient corresponding to each operator.The results indicate that the Wilson coefficients of tensor and scalar operators in the muon sector are in the order of 0(10^(-2))while others are in the order of 0(10^(-3)).The lepton flavor universality could be violated by interactions with the scalar operators.We also determine that the pure leptonic decays are significantly sensitive to scalar operators.The efects of NP on the semi-leptonic decays with electron final state are negligible;however,for the decays with the muon final state,the effects of scalar and tensor operators will appear in the forward-back-ward asymmetries and the muon helicity asymmetries of D→Pμ^(+)Vpμdecays.The future measurements of these de-cays in the BESIII and Belle II experiments will facilitate the evaluation of NP effects.
We study the scalar electrodynamics (S Q E D (4)) and the spinor electrodynamics (Q E D (4)) in the null-plane formalism. We follow Dirac's technique for constrained systems to analyze the constraint structure in both theories in detail. We impose the appropriate boundary conditions on the fields to fix the hidden subset first class constraints that generate improper gauge transformations and obtain a unique inverse of the second-class constraint matrix. Finally, choosing the null-plane gauge condition, we determine the generalized Dirac brackets of the independent dynamical variables, which via the correspondence principle give the (anti)-commutators for posterior quantization.
A method of forming NFET S/D structures with multiple layers, with consecutive epi-SiP layers being doped at increasing dosages of P and the resulting device are provided. Embodiments include forming multiple epi-Si layers in each S/D cavity of a NFET; and performing in-situ doping of P for each epi-Si layer, wherein consecutive epi-Si layers are doped at increasing dosages of P.
Anomalies in decays induced by b→cl-vl(l=e,μ,τ) transitions may imply lepton flavor universality violations,which raises questions on such phenomena in the D decays induced by c→(s,d)l+vl transitions.Current measurements of the pure leptonic and semi-leptonic D decays agree with the standard model(SM) predictions,and such agreements can be used to constrain the new physics(NP) contributions.In this work,we extend SM by assuming general effective Hamiltonians describing the c→(s,d)l+vl transitions including the full set of the four-fermion operators.With the latest experimental data,we perform a least χ~2 fit of the Wilson coefficient corresponding to each operator.The results indicate that the Wilson coefficients of tensor and scalar operators in the muon sector are in the order of O(10-2) while others are in the order of O(10-3).The lepton flavor universality could be violated by interactions with the scalar operators.We also determine that the pure leptonic decays are significantly sensitive to scalar operators.The effects of NP on the semi-leptonic decays with electron final state are negligible;however,for the decays with the muon final state,the effects of scalar and tensor operators will appear in the forward-backward asymmetries and the muon helicity asymmetries of D→Pμ+vμ decays.The future measurements of these decays in the BE SⅢ and Belle Ⅱ experiments will facilitate the evaluation of NP effects.
Using the relativistic Bethe-Salpeter method, the electron energy spectrum and the semileptonic decay widths of B(s)(0) --> D(s)(-)l(+)nu(l) and B(s)(0) --> D(s)*(-)l(+)nu(l) are calculated. We obtain a large branching fraction Br (B(s) --> D(s)e nu(e)) = (2.85 +/- 0.35)% and Br (B(s) --> D(s)*e nu(e)) = (7.09 +/- 0.88)%, which can be easily detected in future experiments.