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Related papers: Systematic Uncertainties in $B_K$ with Improved St…

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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 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 report our light hadron mass calculation based on an increased statistics of 250 quenched gauge configurations on a (48^3 \times 64) lattice at (\beta = 6.5). Quark propagators are calculated for each of these configurations with…

High Energy Physics - Lattice · Physics 2009-10-30 Seyong Kim , Shigemi Ohta

Recent conceptual, algorithmic and technical advances allow numerical simulations of lattice QCD with Wilson quarks to be performed at significantly smaller quark masses than was possible before. Here we report on simulations of two-flavour…

High Energy Physics - Lattice · Physics 2010-02-03 L. Del Debbio , L. Giusti , M. Lüscher , R. Petronzio , N. Tantalo

We present the latest preliminary results of the MILC collaboration's analysis of the light pseudoscalar meson sector. The analysis includes data from new ensembles with smaller lattice spacings, smaller light quark masses and…

We study the impact of an additional $U(1)'$ gauge symmetry with flavour-dependent charges for quarks and leptons on the LHC flavour anomalies observed in $B \to K^* \mu^+\mu^-$, $R(K) = B \to K \mu^+\mu^-/B \to K e^+e^-$, and $h \to…

High Energy Physics - Phenomenology · Physics 2015-04-15 Andreas Crivellin , Giancarlo D'Ambrosio , Julian Heeck

We present recent results from lattice simulations of 2+1 flavors of improved staggered fermions at zero baryon number density near the high temperature crossover. Included are new results from simulations of asqtad fermions at Nt = 12 and…

High Energy Physics - Lattice · Physics 2011-01-27 Wolfgang Söldner

Many results from lattice QCD of broad importance to particle and nuclear physics are obtained with 2+1 flavors of staggered sea quarks. In the continuum limit, staggered fermions yield four species, called tastes. To reduce the number of…

High Energy Physics - Lattice · Physics 2011-06-10 Andreas S. Kronfeld

The s-wave pion-kaon ($\pi K$) scattering lengths at zero momentum are calculated in lattice QCD with sufficiently light $u/d$ quarks and strange quark at its physical value by the finite size formula. The light quark masses correspond to…

High Energy Physics - Lattice · Physics 2012-04-04 Ziwen Fu

We fit lattice-QCD data for light-pseudoscalar masses and decay constants, from HISQ configurations generated by MILC, to SU(3) staggered chiral perturbation theory. At present such fits have rather high values of chi^2/d.o.f., possibly due…

We present an update on our calculation of the short-distance $D^0$-meson mixing hadronic matrix elements. The analysis is performed on the MILC collaboration's $N_f=2+1$ asqtad configurations. We use asqtad light valence quarks and the…

High Energy Physics - Lattice · Physics 2014-12-16 C. C. Chang , C. Bernard , C. M. Bouchard , A. X. El-Khadra , E. D. Freeland , E. Gámiz , A. S. Kronfeld , J. Laiho , R. S. Van de Water

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 the first lattice QCD calculation of the form factor for B-> D* l nu with three flavors of sea quarks. We use an improved staggered action for the light valence and sea quarks (the MILC configurations), and the Fermilab action…

The results of a preliminary partially quenched (N_f=2) study of the light hadron spectrum, renormalization constants and light quark masses are presented. Numerical simulations are carried out with the LL-SSOR preconditioned Hybrid Monte…

High Energy Physics - Lattice · Physics 2010-03-19 D. Becirevic , P. Boucaud , V. Gimenez , V. Lubicz , G. Martinelli , F. Mescia , S. Simula , C. Tarantino

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

One of the most serious problems of the staggered fermion lattice action is flavor symmetry violation. Smeared link staggered fermions can improve flavor symmetry by an order of magnitude relative to the standard thin link action. Over the…

High Energy Physics - Lattice · Physics 2009-11-07 Anna Hasenfratz

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

The feasibility of using lattice chiral fermions which are free of $O(a)$ errors for both the heavy and light quarks is examined. The fact that the effective quark propagators in these fermions have the same form as that in the continuum…

High Energy Physics - Lattice · Physics 2009-11-07 K. F. Liu , S. J. Dong

We report preliminary results from an ongoing calculation of $B_K$ for $N_f=2$ dynamical QCD with domain wall fermions. Simulations have been done with three dynamical quark masses on $16^3 \times 32$ volumes with $L_s = 12$, where the…

High Energy Physics - Lattice · Physics 2019-08-14 Taku Izubuchi

We determine the mass of the lightest quark-antiquark scalar meson with I=1 using the simulation with two dynamical Domain Wall Fermions. The conventional exponential fit of the scalar correlator is justified in this case giving the mass…

High Energy Physics - Lattice · Physics 2007-05-23 S. Prelovsek