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Related papers: The Kaon B-parameter in quenched QCD

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We present results for the Kaon $B$ parameter from a sample of $200$ configurations using the Wilson action and $460$ configurations using the Clover action, on a $18^3 \times 64$ lattice at $\beta=6.0$. A slight improvement of the chiral…

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…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Dimopoulos , J. Heitger , F. Palombi , C. Pena , S. Sint , A. Vladikas

We present an unquenched $N_f=2$ lattice computation of the $B_{K}$ parameter which controls $K^0-\bar K^0$ oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence…

We report our results for the bag-parameter BK obtained from the quenched simulations on the lattice with Wilson fermions at three values of the lattice spacing. We implemented the method by which no subtraction of the mixing with other…

High Energy Physics - Lattice · Physics 2010-03-19 D. Becirevic , Ph. Boucaud , V. Gimenez , V. Lubicz , M. Papinutto

We present a non-perturbative determination of the renormalization factor Z_S of the scalar density in quenched QCD with overlap fermions. Results are obtained at four values of the lattice spacing. By combining Z_S with results for the…

High Energy Physics - Lattice · Physics 2009-11-11 Jan Wennekers , Hartmut Wittig

We compute the mass of the b-quark and the B_s meson decay constant in quenched lattice QCD using a combination of HQET and the standard relativistic QCD Lagrangian. We start from a small volume, where one can directly deal with the…

High Energy Physics - Lattice · Physics 2011-01-27 Damiano Guazzini , Rainer Sommer , Nazario Tantalo

For the first time, we compute non-perturbatively, i.e. without lattice perturbation theory, the renormalization constants of two-fermion operators in the quenched approximation at $\beta=6.0$, 6.2 and 6.4 using the Wilson and the…

High Energy Physics - Phenomenology · Physics 2009-10-31 V. Gimenez

We discuss the renormalization of different definitions of quark masses in the Wilson and the tree-level improved SW-Clover fermionic action. For the improved case we give the correct relationship between the quark mass and the hopping…

High Energy Physics - Lattice · Physics 2009-10-31 V. Gimenez , L. Giusti , F. Rapuano , M. Talevi

We present a fully non-perturbative computation of the mass of the b-quark in the quenched approximation. Our strategy starts from the matching of HQET to QCD in a finite volume and finally relates the quark mass to the spin averaged mass…

High Energy Physics - Phenomenology · Physics 2009-11-11 Michele Della Morte , Nicolas Garron , Mauro Papinutto , Rainer Sommer

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…

High Energy Physics - Lattice · Physics 2011-11-10 S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , T. Kurth , L. Lellouch , T. Lippert , C. McNeile , A. Portelli , K. K. Szabo

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…

High Energy Physics - Lattice · Physics 2008-11-26 F. Palombi , M. Papinutto , C. Pena , H. Wittig

We present results for the kaon $B$-parameter $B_K$ from a sample of $200$ configurations using the Wilson action and $460$ configurations using the SW-Clover action, on a $18^3 \times 64$ lattice at $\beta=6.0$. We compare results obtained…

High Energy Physics - Lattice · Physics 2009-10-28 M. Crisafulli , A. Donini , V. Lubicz , G. Martinelli F. Rapuano , M. Talevi , C. Ungarelli , A. Vladikas

We present a calculation of the kaon $B$-parameter, $B_K$, using lattice QCD. We use improved staggered valence and sea fermions, the latter generated by the MILC collaboration with $N_f=2+1$ light flavors. To control discretization errors,…

We present preliminary results at {\beta} = 1.95 (a = 0.077 fm) on the first unquenched N_f=2+1+1 lattice computation of the B_K parameter which controls the neutral kaon oscillations in the Standard Model. Using N_f=2+1+1 maximally twisted…

High Energy Physics - Lattice · Physics 2011-11-08 N. Carrasco , V. Gimenez , P. Dimopoulos , R. Frezzotti , D. Palao , G. C. Rossi , V. Lubicz , M. Papinutto , F. Sanfilippo , S. Simula

We present new results of our ongoing project toward a precision determination of the kaon $B$ parameter with the Kogut-Susskind quark action in quenched QCD. New results taken at $\beta$=6.4 and $\beta=5.7$ suggest that an apparently…

High Energy Physics - Lattice · Physics 2009-10-28 JLQCD Collaboration , S. Aoki , M. Fukugita , S. Hashimoto , N. Ishizuka , Y. Iwasaki , K. Kanaya , Y. Kuramashi , H. Mino , M. Okawa , A. Ukawa , T. Yoshie

We present results of a high statistics study (O(2000) configurations) of the quark masses in the MS-bar scheme from Lattice QCD in the quenched approximation at beta=6.0, beta=6.2 and beta=6.4 using both the Wilson and the tree-level…

High Energy Physics - Lattice · Physics 2009-10-30 L. Giusti

A lattice QCD calculation of the B meson decay constant is presented. In order to investigate the scaling violation associated with the heavy quark, parallel simulations are carried out employing both Wilson and the O(a)-improved clover…

High Energy Physics - Lattice · Physics 2007-05-23 JLQCD collaboration , S. Aoki , M. Fukugita , S. Hashimoto , N. Ishizuka , Y. Iwasaki , K. Kanaya , Y. Kuramashi , M. Okawa , A. Ukawa , T. Yoshié

We present a determination of the QCD parameter Lambda in the quenched approximation (n_f=0) and for two flavours (n_f=2) of light dynamical quarks. The calculations are performed on the lattice using O(a) improved Wilson fermions and…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Göckeler , R. Horsley , A. C. Irving , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben

We compute on the lattice the ``bag'' parameters of the five (Delta B = 2) operators of the supersymmetric basis, by combining their values determined in full QCD and in the static limit of HQET. The extrapolation of the QCD results from…

High Energy Physics - Lattice · Physics 2009-11-07 D. Becirevic , V. Gimenez , G. Martinelli , M. Papinutto , J. Reyes

We show that the renormalization factor relating the renormalization group invariant quark masses to the bare quark masses computed in lattice QCD can be determined non-perturbatively. The calculation is based on an extension of a…

High Energy Physics - Lattice · Physics 2009-10-30 S. Capitani , M. Guagnelli , M. Luescher , S. Sint , R. Sommer , P. Weisz , H. Wittig