Related papers: Calculating $B_K$ using HYP staggered fermions

We review recent results for B_d and B_s mixing parameters using MILC N_f=2+1 lattices, NRQCD b-quarks and AsqTad light quarks. Latest numbers for decay constants f_B and f_{B_s} are also presented. Combining our lattice results with…

We present determinations of the B meson decay constant f_B and of the ratio f_{B_s}/f_B using the MILC collaboration unquenched gauge configurations which include three flavors of light sea quarks. The mass of one of the sea quarks is kept…

We computed the B_K parameter on the lattice by using a non-perturbatively improved Wilson action. From our quenched simulation, in the MSbar scheme and at mu=2 GeV, we obtain B_K=0.73(7)^{+0.05}_{-0.01}. To gain some insight in the…

We calculate the fermion self-energy at O(alpha_s) for the Symanzik improved staggered fermion action used in recent lattice simulations by the MILC collaboration. We demonstrate that the algebraic approach to lattice perturbation theory,…

We report on our first experiences in simulating Neuberger valence fermions on CLS $N_f=2$ configurations with light sea quark masses and small lattice spacings. Valence quark masses are considered that allow to explore the matching to…

We calculate the kaon $B$-parameter in quenched lattice QCD at $\beta=6.0$ using Wilson fermions at $\kappa=0.154$ and $0.155$. We use two kinds of non-local (``smeared'') sources for quark propagators to calculate the matrix elements…

Semileptonic, B --> pi l,nu, decays are studied on the MILC dynamical configurations using NRQCD heavy and Asqtad light quarks. We work with light valence quark masses ranging between m_s and m_s/8. Preliminary simple linear chiral…

The cost of dynamical quark simulations with improved staggered quarks is estimated based on current and planned running by the MILC collaboration. I find that a few 10s of Teraflop years should be sufficient to calculate down to a lattice…

We report on investigations of the chiral and deconfinement aspects of the finite temperature transition in 2+1 flavor QCD using the Highly Improved Staggered Quark (HISQ) action on lattices with temporal extent $N_\tau=6$ and $N_\tau=8$.…

We consider partially quenched, mixed chiral perturbation theory with staggered sea and Ginsparg-Wilson valence quarks in order to extract a chiral-continuum extrapolation expression for the vector meson mass up to order O(a^2), at one-loop…

We report on a calculation of $B_K$ with two-flavor dynamical overlap fermions on a $16^3 \times 32$ lattice at $a\sim 0.12$ fm. The results are compared with the PQChPT prediction of quark mass dependence. The systematic errors due to…

We study the properties of the B-->pi and B-->K transition form factors in partially quenched QCD by using the approach of partially quenched chiral perturbation theory combined with the static heavy quark limit. We show that the form…

We present an update of HPQCD's lattice QCD determination of the $B_c\to J/\psi$ vector and axial-vector form factors, and provide new results for the tensor form factors. We use the Highly Improved Staggered Quark action for all valence…

Lattice matrix elements are briefly reviewed. In the quenched approximation $f_B$, $B_B$ and $B_K$ are now under good control. Experimental hints for $f^{\rm expt}_{D_S}> f^{\rm QQCD}_{D_S}$ are noted; precise determination of $f_{D_S}$…

Using the MILC 2+1 flavor asqtad quark action ensembles, we are calculating the form factors $f_0$ and $f_+$ for the semileptonic $B_s \rightarrow K \ell\nu$ decay. A total of six ensembles with lattice spacing from $\approx0.12$ to 0.06 fm…

We present preliminary results for $\epsilon'/\epsilon$ calculated using HYP staggered fermions in the quenched approximation. We compare different choices of quenched penguin operators.

We simulate two dynamical, mass degenerate light quarks on 16^3x32 lattices with a spatial extent of 2.4 fm using the Chirally Improved Dirac operator. The simulation method, the implementation of the action and signals of equilibration are…

We report calculations of B_K using two flavours of dynamical clover-improved Wilson lattice fermions and look for dependence on the dynamical quark mass at fixed lattice spacing. We see some evidence for dynamical quark effects. In…

We present preliminary results of light hadron spectroscopy using valence, tadpole-improved, Clover fermions on an ensemble of gauge configurations generated with 2 flavors of staggered fermions at a beta of 5.6. We compare the slope and…

We report on progress of a lattice QCD calculation of the $B\to Dl\nu$ and $B_s\to D_s l\nu$ semileptonic form factors. We use a relativistic staggered action (HISQ) for light and charm quarks, and an improved non-relativistic (NRQCD)…