相关论文: The Kaon B-parameter with the Wilson Quark Action …
We calculate the $B_{B}$ parameter, relevant for $\overline{B}^0$ -- $B^0$ mixing, from a lattice gauge theory simulation at $\beta = 6.0$. The bottom quarks are simulated in the static theory, the light quarks with Wilson fermions.…
We present non-perturbative renormalization factors for $\Delta S=2$ four-quark operators in quenched domain-wall QCD using the Schroedinger functional method. Non-perturbative renormalization factor for $B_K$ is evaluated at hadronic…
A new QCD calculation of the B parameter of $K^{0}-\bar{K^{0}}$ mixing is presented. It makes use of polynomial kernels in dispersion integrals in order to practically eliminate the contributions of the unknown pseudoscalar strange…
It is shown that the renormalisation constants of two quark operators can be accurately determined (to a precision of a few per-cent using 18 gluon configurations) using Chiral Ward identities. A method for computing renormalisation…
Indirect CP violation in K \rightarrow {\pi}{\pi} decays plays a central role in constraining the flavor structure of the Standard Model (SM) and in the search for new physics. For many years the leading uncertainty in the SM prediction of…
We study the B-parameter (``bag factor'') for B-anti-B mixing within a recently developed heavy-light chiral quark model. Non-factorizable contributions in terms of gluon condensates and chiral corrections are calculated. In addition, we…
We report on a non-perturbative study of the scale-dependent renormalization factors of a multiplicatively renormalizable basis of Delta B=2 parity-odd four-fermion operators in quenched lattice QCD. We also present some preliminary results…
We compute O(alpha_s) lattice-to-continuum perturbative matching coefficients for the Delta S=2 flavor changing four-quark operators for the Asqtad improved staggered action. In conjunction with lattice simulations with three flavors of…
We report on the calculation of the kaon B-parameter using two dynamical flavours of domain wall fermions. Our analysis is based on three ensembles of configurations, each consisting of about 5,000 HMC trajectories, with a lattice spacing…
We study the improvement of staggered fermions using hypercubically smeared (HYP) links. We calculate the strange quark mass and the kaon B-parameter, $B_K$, in quenched QCD on a $16^3 \times 64$ lattice at $\beta=6.0$. We find…
We make a comparison between our quenched-hadron-spectroscopy results for the non-perturbatively-improved Wilson action and the corresponding unimproved case, at beta=6.2 on the same set of gauge configurations. Within our statistics, we…
In the limit of infinitely heavy b-quarks we compute the SU(3)-breaking ratio xi of neutral B-meson mixing matrix elements. We also present results for the ratio of decay constants f_{B_s}/f_{B_d}. Our calculation employs…
We consider the problem of determining the matrix element of the heavy quark kinetic energy operator between $\Lambda_b$ baryonic states by three point function QCD sum rules in the Heavy Quark Effective Theory. We discuss the main features…
We give a progress report of our new $a^{-1}\approx 3$ GeV quenched calculation of kaon matrix elements with domain-wall fermion and DBW2 gauge action. Our smaller lattice spacing allows us to address the effect of charmed quark on the…
Improved results for $B_K$ are discussed. Scaling corrections are argued to be of $O(a^2)$, leading to a reduction in the systematic error. For a kaon composed of degenerate quarks, the quenched result is ${\widehat{B}_K} = 0.825 \pm 0.027…
The $B_K$ parameter is computed in quenched lattice QCD with Wilson twisted mass fermions. Two variants of tmQCD are used; in both of them the relevant $\Delta S = 2$ four-fermion operator is renormalised multiplicatively. The…
The QCD finite energy sum rules method is used to show that the parameter of the K^0-\bar{K}_0 mixing \hat{B} is mainly determined by the value of g m_s< \bar{d} G_{\mu\nu} \sigma_{\mu\nu} d > and the vacuum expectation values of four-quark…
A report is presented on our continued effort to elucidate the continuum limit of $B_K$ using the quenched Kogut-Susskind quark action. By adding to our previous simulations one more point at $\beta = 6.65$ employing a $56^3\times 96$…
We study scaling behavior of a chiral order parameter performing a simulation of two-flavor QCD with improved Wilson quarks. It has been shown that the scaling behavior of the chiral order parameter defined by a Ward-Takahashi identity…
Renormalization factors for three- and four-quark operators, which appear in the low energy effective Lagrangian of the proton decay and the weak interactions, are perturbatively calculated in domain-wall QCD. We find that the operators are…