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Related papers: Calculating $B_K$ using HYP staggered fermions

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We calculate the B -> D and B -> D* form factors at zero recoil in Staggered Chiral Perturbation Theory. We consider heavy-light mesons in which only the light (u, d, or s) quark is staggered; current lattice simulations generally use a…

High Energy Physics - Lattice · Physics 2008-11-26 Jack Laiho , Ruth S. Van de Water

We present results for $B_{(s)}$- and $D_{(s)}$-meson semileptonic decays from ongoing calculations by the Fermilab Lattice and MILC Collaborations. Our calculation employs the highly improved staggered quark (HISQ) action for both sea and…

We report on the status of our kaon semileptonic form factor calculations using the highly-improved staggered quark (HISQ) formulation to simulate the valence fermions. We present results for the form factor f_+^{K \pi}(0) on the asqtad…

I present first results from an in-progress calculation of B_K in quenched approximation using overlap fermions. My particular implementation of the overlap uses a kernel with nearest and next-nearest neighbor interactions and HYP-blocked…

High Energy Physics - Lattice · Physics 2015-06-25 Thomas DeGrand

We present a two-flavor QCD calculation of $B_K$ on a $16^3 \times 32$ lattice at $a\sim 0.12$ fm (or equivalently $a^{-1}\sim$1.67 GeV). Both valence and sea quarks are described by the overlap fermion formulation. The matching factor is…

High Energy Physics - Lattice · Physics 2019-08-13 S. Aoki , H. Fukaya , S. Hashimoto , J. Noaki , T. Kaneko , H. Matsufuru , T. Onogi , N. Yamada

Models of new physics induce K-Kbar mixing operators having Dirac structures other than the "left-left" form of the Standard Model. We calculate the functional form of the corresponding B-parameters at next-to-leading order in both SU(3)…

High Energy Physics - Lattice · Physics 2013-05-30 Jon A. Bailey , Hyung-Jin Kim , Weonjong Lee , Stephen R. Sharpe

We report on results from three spectrum calculations with staggered quarks: 1) a quenched calculation with the standard action for the gluons and quarks; 2) a quenched calculation with improved actions for both the gluons and quarks; and…

We present recent progress in understanding weak matrix elements on the lattice. We use HYP staggered fermions in quenched QCD to study numerically various properties of the $K^+\to\pi^+$ amplitudes of the electroweak penguin operators…

High Energy Physics - Lattice · Physics 2007-05-23 Weonjong Lee , George T. Fleming

We calculate the kaon B-parameter, B_K, to next-to-leading order in staggered chiral perturbation theory. We extend the usual power counting to include the effects of using perturbative (rather than non-perturbative) matching factors. Taste…

High Energy Physics - Lattice · Physics 2007-05-23 Ruth S. Van de Water , Stephen R. Sharpe

Calculations of B leptonic decays and B- bar B mixing using NRQCD heavy and Asqtad light valence quarks on the MILC dynamical configurations are described. Smearing has been implemented to substantially reduce the statistical errors of the…

High Energy Physics - Lattice · Physics 2009-11-10 A. Gray , C. Davies , E. Gulez , G. P. Lepage , J. Shigemitsu , M. Wingate

We compute pseudoscalar meson masses and decay constants using staggered quarks on lattices with three flavors of sea quarks and lattice spacings $\approx 0.12$ fm and $\approx 0.09$ fm. We fit partially quenched results to ``staggered…

Although taste violations significantly affect the results of staggered calculations of pseudoscalar and heavy-light mesonic quantities, those entering staggered calculations of baryonic quantities have not been quantified. Here I develop…

High Energy Physics - Lattice · Physics 2008-11-26 Jon A. Bailey

We discuss the matching procedure for heavy-light 4-quark operators using the Fermilab method for heavy quarks and staggered fermions for light quarks. These ingredients enable us to construct the continuum-limit operator needed to…

High Energy Physics - Lattice · Physics 2010-11-05 Richard Todd Evans , Elvira Gamiz , Aida El-Khadra , Andreas Kronfeld

The MILC collaboration's simulations with improved staggered quarks are being extended with runs at a lattice spacing of 0.06 fm with quark masses down to one tenth the strange quark mass. We give a brief introduction to these new…

High Energy Physics - Lattice · Physics 2010-11-15 C. Bernard , C. Davies , C. DeTar , Steven Gottlieb , U. M. Heller , J. E. Hetrick , L. Levkova , J. Osborn , D. B. Renner , R. Sugar , D. Toussaint

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

High Energy Physics - Lattice · Physics 2025-02-05 Judd Harrison

We calculate one-loop matching factors for bilinear operators composed of improved staggered fermions. We compare the results for different improvement schemes used in the recent literature, including the HYP action and an action close to…

High Energy Physics - Lattice · Physics 2009-11-07 Weonjong Lee , Stephen R. Sharpe

This work continues our program of lattice-QCD baryon physics using staggered fermions for both the sea and valence quarks. We present a proof-of-concept study that demonstrates, for the first time, how to calculate baryon matrix elements…

High Energy Physics - Lattice · Physics 2021-03-03 Yin Lin , Aaron S. Meyer , Steven Gottlieb , Ciaran Hughes , Andreas S. Kronfeld , James N. Simone , Alexei Strelchenko

Using the lattice simulations in the Asqtad-improved staggered fermion formulation we compute the point-to-point $\kappa$ correlators, which are analyzed by the rooted staggered chiral perturbation theory (rS$\chi$PT). After chiral…

High Energy Physics - Lattice · Physics 2013-06-03 Ziwen Fu

We present results for one-loop perturbative matching factors using bilinear operators composed of improved staggered fermions, using unimproved (Wilson) and improved (Symanzik, Iwasaki, and DBW2) gluon actions. We consider two fermions…

High Energy Physics - Lattice · Physics 2012-01-25 Jongjeong Kim , Weonjong Lee , Stephen R. Sharpe

We present preliminary results from UKQCD simulations at light quark masses using two flavours of non-pertubatively improved Wilson fermions. We report on the performance of the standard HMC algorithm at these quark masses where m_pi/m_rho…

High Energy Physics - Lattice · Physics 2015-06-25 A. C. Irving , UKQCD Collaboration