Related papers: $(B+L)$-conserving Nucleon Decays in Supersymmetri…
High Luminosity upgrades of the KEK-B collider are being discussed. We consider the role of the purely leptonic decays B^\pm -> l^\pm nu and B^0 -> l+l- in motivating such an upgrade. These decays are very sensitive to R parity violating…
We investigate leptonic decays $D_s \to \tau \nu_\tau$ and $B^+ \to \tau \nu_\tau$ in R-parity violating (RPV) supersymmetric standard model. Taking account of interference between the s-channel slepton exchange and the $t$-channel squark…
The general analysis of lepton polarization asymmetries in rare B -> K^* l^+ l^- decay is investigated. Using the most general, model independent effective Hamiltonian, the general expressions of the longitudinal, normal and transversal…
We study the rare decays $B^{+}_u\to \pi^{+}\ell^{+}\ell^{-}$, $\rho^{+}\ell^{+}\ell^{-}$ and $B^{0}_d \to \ell^{+} \ell^{-}(\ell=e,\mu)$ in the R-parity violating supersymmetric standard model. From the latest upper limits of…
I present a supersymmetric theory of flavor based on the discrete flavor group $(S_3)^3$. The model can account for the masses and mixing angles of the standard model, while maintaining sufficient sfermion degeneracy to evade the…
We study rare exclusive B decays based on the quark-level transition b->s(d)l^+l^-, where l=e or mu, in the context of supersymmetric theories with minimal flavour violation. We present analytic expressions for various mixing matrices in…
The branching ratio of the $K^+\to\pi^+e^+e^-e^+e^-$ ($K^+\to\pi^+4e$) decay is calculated at leading order in the Standard Model. The dominance of the neutral-pion pole determines the overall branching ratio to be…
A model-independent analysis for the exclusive, rare B -> pi^+ pi^- l^+ l^- decay is presented. The dependence of the various physically measurable asymmetries and CP violating asymmetry on the new Wilson coefficients is studied in detail.…
We report a study of the modes D_CP K+- and D^*_CP K+- where D^(*) decays to CP eigenstates. The data sample used contains 275 x 10^6 BB events at the Upsilon(4S) resonance collected by the Belle detector at the KEKB energy-asymmetric e^+…
We report a search for the rare decays $B^+ \to D^+ K^0$ and $B^+ \to D^+ K^{*0}$ in an event sample of approximately 465 million $B\bar B$ pairs collected with the BaBar detector at the PEP-II asymmetric-energy $e^+e^-$ collider at SLAC.…
The decay $K_L \to \gamma \nu \bar{\nu}$ is investigated beyond the standard model. Interestingly, the upper limit of the CP-conserving and CP-violating branching ratios of the decay, induced from the possible extensions of the standard…
The flavor changing neutral current processes $K_L \to \pi^0 e^+ e^-$, $B \to X_s e^+ e^-$ and $B \to X_s \mu^+ \mu^-$ are studied within the minimal supersymmetric extension of the Standard Model. We first examine the rates for these decay…
We report a study of the decay $B^0\rightarrow D K^+\pi^-$ followed by $D\rightarrow K^-\pi^+$, where $D$ indicates $D^0$ or $\bar{D}^0$. We reconstruct the $D K^+\pi^-$ state in a phase space corresponding to $D K^{*}(892)^0$. The…
We study Z--> l^+ l^- and W--> nu_l l^+ decays in the standard model including the noncommutative effects. We observe that these effects appear in the flavor dependent part of the decay widths of the processes under consideration and…
We perform the first search for lepton-number-violating B+->D-l+l'+ decays, where l and l' stand for e or mu, using 772 x 10^6 BB-bar pairs accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB e^+e^- collider. No…
We study some rare B decays induced by $b \to s$ transition within the Standard Model and in the Appelquist-Cheng-Dobrescu model, which is a New Physics scenario with a single universal extra dimension. In particular, we discuss the…
Recently, the LHC has found several anomalies in exclusive semileptonic b --> s l^+ l^- decays. In this proceeding, we summarize the most important results of our global analysis of the relevant decay modes. After a discussion of the…
In the Standard Model, no dim-5 $\Delta B \neq 0$ operators exist, so that Planck-scale-induced proton decay amplitudes are suppressed by at least $1/M^2_{P \ell}$. If the Standard Model is augmented by a light, color-non-singlet boson,…
Decays of B mesons into final states containing a tau lepton are sensitive to new charged-current interactions that break lepton-flavor universality. These decays have been studied only at e+e- colliders, where the low-background…
At present, there are several measurements of $B$ decays that exhibit discrepancies with the predictions of the SM, and suggest the presence of new physics (NP) in $b \to s \mu^+ \mu^-$ transitions. Many NP models have been proposed as…