Related papers: Helicity amplitudes in $B \to D^{*} \bar{\nu} l$ d…
We present results of the first lattice QCD calculations of $B_c \to B_s$ and $B_c \to B_d$ weak matrix elements. Form factors across the entire physical $q^2$ range are then extracted and extrapolated to the physical-continuum limit before…
Studies of D and B mesons decays into hadrons have been used to test the standard model in the last fifteen years. A heavy meson decay involves the combined effects of a primary weak vertex and subsequent hadronic final state interactions,…
At the kinematic endpoint of zero recoil physical momenta are parallel which leads to symmetries in the decay distributions. We implement this observation for decays of the type $A \to (B_1 B_2) C$ by extending the helicity formalism to…
Measurements of the rates for the hadronic decays B^+- -> pi K can be used to derive information on the weak phase gamma=arg(V_ub^*) in a largely model-independent way. Hadronic uncertainties can be reduced to the level of nonfactorizable…
We find expressions for the weak decay amplitudes of baryons containing two b quarks (or one b and one c quark -- many relationship are the same) in terms of unknown reduced matrix elements. This project was originally motivated by the…
The independent helicity amplitudes in the (Lambda_b -> \Lambda l^+ l^-) decay in the standard model and its minimal extension, i.e., with the new vector type interactions, are calculated. We calculate various asymmetry parameters…
This talk presents results of weak matrix elements calculated from simulations done on 170 $32^3 \times 64$ lattices at $\beta = 6.0$ using quenched Wilson fermions. We discuss the extraction of pseudoscalar decay constants $f_\pi$, $f_K$,…
We discuss the amplitude of the $B\to l^+l^-l'\nu'$ decays and the differential decay rate $d^2\Gamma/dq^2dq'^2$, $q$ the momentum of the $l^+l^-$ pair emitted from the electromagnetic vertex and $q'$ the momentum of the $l'\nu'$ pair…
We compute the Standard Model semileptonic vector and axial-vector form factors for $B_s\to D_s^*$ decay across the full $q^2$ range using lattice QCD. We use the Highly Improved Staggered Quark (HISQ) action for all valence quarks,…
A short review of our recent work on amplitude parametrizations of three-body hadronic weak $B$ and $D$ decays is presented. The final states are here composed of three light mesons, namely the various charge $\pi\pi\pi$, $K\pi\pi$ and…
We explore the sensitivity of the flavour changing neutral currents among c and u quarks in the context of the Minimal Supersymmetric Standard Model. The standard model rate for c->u gamma can be enhanced by up to two orders of magnitudes…
A new model-independent parametrization is proposed for the hadronic form factors in the semileptonic $\bar{B}\to D\ell\bar{\nu}_\ell$ decay. By a combined consideration of the recent experimental and lattice QCD data, we determine…
The hadronic weak decays of $\Lambda_c$ are studied in the framework of a constituent quark model. With the combined analysis of the Cabbibo-favored processes, $\Lambda_c\to \Lambda\pi^+$, $\Sigma^0\pi^+$ and $\Sigma^+\pi^0$, we confirm…
A QCD relativistic potential model is employed to compute the decay rate and the photon spectrum of the process $B^- \to \mu^- {\bar \nu}_\mu \gamma$. The result ${\cal B}(B^- \to \mu^- {\bar \nu}_\mu \gamma) \simeq 1 \times 10^{-6}$…
We determine the weak coupling |Vcb| between the b and c quarks using a sample of 3 million BB-bar events in the CLEO detector at the Cornell Electron Storage Ring. We determine the yield of reconstructed B --> D* l nu decays as a function…
We investigate helicity amplitudes (HAs) of $A \to B C$-type decays for arbitrary spin towards the kinematic endpoint. We show that they are proportional to product of Clebsch-Gordan coefficients (CGC) and the velocity to some positive…
Our understanding of the low-lying resonance structure in $^{12}$C remains incomplete. We have used the $^{11}\text{B}(p,3\alpha)\gamma$ reaction at proton energies of $E_p=0.5-2.7$ MeV as a selective probe of the excitation region above…
We analyse the form factors for the B --> gamma l^+l^- weak transition. We show that making use of the gauge invariance of the B --> gamma l^+l^- amplitude, the structure of the form factors in the resonance region, and their relations at…
The photoleptonic decay $B^-\to \gamma \ell^-\bar{\nu}$ is the simplest low-energy process that probes the substructure of the $B$ meson, making it an excellent candidate to determine the parameters of $B$-meson light-cone distribution…
A general parametrization of the amplitudes for the rare two-body decays B -> pi K is introduced, which makes maximal use of theoretical constraints arising from flavour symmetries of the strong interactions and the structure of the…