相关论文: T violation in $\Lambda_b\to\Lambda\ell^+\ell^-$ d…
In supersymmetric theories with R-parity violation, squarks and sleptons can mediate Standard Model fermion-fermion scattering processes. These scalar exchanges in e+e- initiated reactions can give new signals at future linear colliders. We…
I review the theoretical basis of the prediction that the decay K_L -> pi+ pi- e+ e- should show a large CP- and T-violation, a prediction now confirmed by the KTeV experiment. The genesis of the effect lies in a large violation of CP- and…
We show that the CP-violating dipole form factors of the tau lepton can be of the order of $\alpha/\pi$ in units of the length scale set by the inverse $Z$ boson mass. We propose a few observables which are sensitive to these form factors…
We study the exclusive decays of $B\to K^{(*)}\ell^+ \ell^-$ by the results in the perturbative QCD with the heavy quark effective theory and lattice calculations. We obtain the form factors for the $B\to K^{(*)}$ transitions in the whole…
We study the forward-backward and the CP-violating asymmetries (both time-independent and time-dependent) in rare semileptonic $B_d\to\rho^0 l^+l^-$, $B_s\to\phi l^+l^-$, and radiative leptonic $B_{d,s}\to \gamma l^+l^-$ decays and…
The paper gives the polarization of the tau lepton in the semileptonic B decays with respect to the direction of the virtual W boson. The result is given including the nonperturbative HQET corrections.The perturbative QCD corrections are…
We have searched for tau lepton decays, tau- -> Lambda-bar pi- and tau- -> Lambda pi-, that simultaneously violate the conservation of the lepton and baryon number using a data sample of 154 fb^{-1} collected with the Belle detector at the…
We review the direct CP and T violation in the three-body baryonic B decays in the standard model. In particular, we emphasize that the direct CP violating asymmetry in $B^\pm\to p\bar p K^{*\pm}$ is around 22% and the direct $T$ violating…
We derive the upper bounds on certain products of R-parity- and lepton-flavor-violating couplings from $B^\pm \to l^\pm \nu$ decays. These modes of B-meson decays can constrain the product combinations of the couplings with one or more…
Rare $b \to s\ell^+\ell^-$ flavour-changing-neutral-current processes provide important tests of the Standard Model of particle physics. Angular observables in exclusive $b \to s\ell^+\ell^-$ processes can be particularly powerful as they…
Models with explicit R-parity violation can induce new rare radiative decay modes of the $W$ boson into single supersymmetric particles which also violate lepton number. We examine the rate and signature for one such decay, $W\rightarrow…
Direct CP violations in $B_{l4}$ decays ($B^\pm \to \pi^+\pi^- l^\pm {\nu}_l$) are investigated within the Standard Model (SM) and also in its extensions. In the decay processes, we include various excited states as intermediate states…
T-odd correlations of polarizations and momenta provide a promising testing ground for new physics beyond the standard model. We estimate the contribution of the minimal supersymmetric extension of the standard model to two such…
We study the differential decay rate for the rare $\Lambda_b \to \Lambda (\to N \pi)\ell^+\ell^-$ transition, including a determination of the complete angular distribution, assuming unpolarized $\Lambda_b$ baryons. On the basis of a…
In this work we will study the polarizations of both leptons ($\tau$) in the decay channel $B\to K^* \tau^- \tau^+$. In the case of the dileptonic inclusive decay $B\to K^* \ell^- \ell^+$, where apart from the polarization asymmetries of…
We discuss lepton flavour violating signals at the LHC in the framework of supersymmetric theories. We consider R-parity conserving as well as R-parity violating scenarios. In the case of R-parity conservation we show that in decays of…
We study the T odd correlations induced by CP violating anomalous top-quark couplings at both production and decay level in the process gg --> t t_bar --> (b mu+ nu_mu) (b_bar mu- nu_mu_bar). We consider several counting asymmetries at the…
We investigate the role of $\tau$-lepton polarization in ultraperipheral heavy-ion collisions (UPCs) as a novel application of the intense electromagnetic fields generated in such processes. In particular, we analyze the decay distributions…
We employ OPE techniques within HQET to calculate the inclusive semileptonic decays of polarized $\Lambda_b$ baryons. Lepton mass effects are included which enables us to also discuss rates into polarized $\tau$-leptons. We present explicit…
The longitudinal polarization, the transverse polarization, and the forward-backward asymmetry of Lambda baryons have been measured using a sample of 4.34 million hadronic Z^0 decays collected with the OPAL detector at LEP between 1990 and…