相关论文: Weak transition matrix elements from finite-volume…
Rates and CP asymmetries of the non-leptonic two-body decay of $B_c$ are calculated based on the low energy effective Hamiltonian. We concentrate on such $b$ quark decays of the processes with $0^-$ and $1^-$ S-wave particles and/or $0^+$…
We discuss strategies to determine hadronic decay couplings from lattice studies. As an application, we explore the decay of a vector meson to two pseudoscalar mesons with $N_f=2$ flavours of sea quark. Although we are working with quark…
The rare decays of mesons are higher order effects in weak interactions. The main contributions to such decay processes are from the Z-penguin, the photonpenguin and the box diagram. At the quark level, these contributions are well known.…
We present results of several numerical studies with Wilson fermions relevant for kaon physics. We compute the B_K parameter by using two different methods and extrapolate to the continuum limit. Our preliminary result is B_K(2…
I review lattice calculations and results for hadronic parameters relevant for kaon physics, in particular the vector form factor f+(0) of semileptonic kaon decays, the ratio fK/fpi of leptonic decay constants and the kaon bag parameter BK.…
Quantum chromodynamics (QCD) effects in the semileptonic decay b -> c l nu are evaluated to the second order in the coupling constant, O(alpha_s^2), and to several orders in the expansion in quark masses, m_c/m_b. Corrections are calculated…
We summarize some of the difficulties that confront lattice calculations of non-leptonic kaon decay matrix elements. We review some of the methods that have been proposed to overcome these difficulties, and discuss the importance of…
We discuss one-particle inclusive B decays in the limit of heavy b and c quarks. Using the large-N_C limit we factorize the non-leptonic matrix elements, and we employ a short distance expansion. Modeling the remaining nonperturbative…
We report results (on an intermediate statistics sample) of a study of weak semi-leptonic formfactors of $B$ and $D$ decays, addressing the uncertainties from mass extrapolations to chiral and to heavy quarks. Moreover, we present a…
Recent developments in lattice QCD calculation of weak matrix elements involving light quarks are described. We focus on four topics: $B_K$ with the Kogut-Susskind and Wilson quark actions, $\Delta I=1/2$ rule, proton decay matrix elements…
The rare kaon decay $K^+\to\pi^+\nu\bar{\nu}$ is an ideal process in which to search for signs of new physics and is the primary goal of the NA62 experiment at CERN. In this paper we report on a lattice QCD calculation of the long-distance…
I discuss strategies to determine hadronic decay couplings from lattice studies. As a check of the methods, I explore the decay of a vector meson to two pseudoscalar mesons with $N_f=2$ flavours of sea quark. Although we are working with…
We present preliminary results for the $\Delta I = 3/2$ kaon decay matrix elements using domain wall fermions and the DBW2 gauge action at one coarse lattice spacing corresponding to $a^{-1} = 1.3$ GeV. We employ an extention of the…
Neutrinoless double-$\beta$ ($0\nu\beta\beta$) decay of certain atomic isotopes, if observed, will have significant implications for physics of neutrinos and models of physics beyond the Standard Model. In the simplest scenario, if the mass…
Hyperon decays present a promising alternative for extracting $\vert V_{us} \vert$ from lattice QCD combined with experimental measurements. Currently $\vert V_{us} \vert$ is determined from the kaon decay widths and a lattice calculation…
We present a numerical computation of matrix elements of DI=3/2 K-->pi pi decays by using Wilson fermions. In order to extrapolate to the physical point we work at unphysical kinematics and we resort to Chiral Perturbation Theory at the…
The rare kaon decays $K\to\pi\ell^+\ell^-$ and $K\to\pi\nu\bar{\nu}$ are flavor changing neutral current (FCNC) processes and hence promising channels with which to probe the limits of the standard model and to look for signs of new…
We review the physics of purely leptonic decays of $\pi^\pm$, $K^\pm$, $D^{\pm}$, $D_s^\pm$, and $B^\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of…
We calculate $\Delta I = 3/2$ kaon decay matrix elements using domain wall fermions and the DBW2 gauge action at one coarse lattice spacing corresponding to $a^{-1} = 1.3$ GeV. We employ the Lellouch and L\"uscher formula and its extention…
Leptonic and semileptonic kaon decays represent till now the golden modes for the extraction of the Cabibbo angle from experiments, provided the relevant hadronic quantities, namely the ratio of the kaon and pion leptonic decay constants,…