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Related papers: B-parameters of 4-fermion operators from lattice Q…

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We presents results for the matrix elements of a variety of four-fermion operators calculated using quenched Wilson fermions. Our simulations are done on 170 lattices of size $32^3 x 64$ at $\beta = 6.0$. We find $B_K=0.74 +- 0.04 +- 0.05$,…

High Energy Physics - Lattice · Physics 2008-02-03 Rajan Gupta , Tanmoy Bhattacharya , Stephen Sharpe

We present the results of a precision computation of B_K with Wilson fermions. Simulations are performed at different lattice spacings, enabling continuum limit extrapolations. Two different twisted mass QCD (tmQCD) regularisations are…

High Energy Physics - Lattice · Physics 2007-05-23 P. Dimopoulos , J. Heitger , C. Pena , S. Sint , A. Vladikas

We present a status report on simulations being done on $32^3 \times 64$ lattices at $\beta = 6.0$ using quenched Wilson fermions. Results for the spectrum, decay constants, the kaon B-parameter $B_K$, and semi-leptonic form factors are…

High Energy Physics - Lattice · Physics 2010-05-27 Tanmoy Bhattacharya , Rajan Gupta

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…

High Energy Physics - Lattice · Physics 2009-10-22 Gupta , Daniel , Kilcup , Patel , Sharpe

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 compute several matrix elements of dimension-six four-fermion operators and extract their B-parameters. The calculations have been performed with the tree-level Clover action at $\beta = 6.0$. The renormalization constants and mixing…

High Energy Physics - Lattice · Physics 2016-09-01 L. Conti , A. Donini , V. Gimenez , G. Martinelli , M. Talevi , A. Vladikas

We present a lattice QCD computation of the b-quark mass, the B and B_s decay constants, the B-mixing bag parameters for the full four-fermion operator basis as well as determinations for \xi and f_{Bq}\sqrt{B_i^{(q)}} extrapolated to the…

The kaon B parameter is calculated in quenched lattice QCD with the Wilson quark action. The mixing problem of the \Delta s=2 four-quark operators is solved non-perturbatively with full use of chiral Ward identities, and this method enables…

High Energy Physics - Lattice · Physics 2019-08-17 JLQCD Collaboration , S. Aoki , M. Fukugita , S. Hashimoto , N. Ishizuka , Y. Iwasaki , K. Kanaya , Y. Kuramashi , M. Okawa , A. Ukawa , T. Yoshié

We present preliminary results of $B_K$ calculated using improved staggered fermions with the mixed action (valence quarks = HYP staggered fermions and sea quarks = AsqTad staggered fermions). We analyze the data based upon the prediction…

High Energy Physics - Lattice · Physics 2007-05-23 Jongjeong Kim , Taegil Bae , Weonjong Lee

There are at least two methods to calculate $ B_K $ with staggered fermions: one is the two spin trace formalism and the other is the one spin trace formalism. We have performed numerical simulations on a $ 16^3 \times 40 $ lattice in full…

High Energy Physics - Lattice · Physics 2010-11-01 Weonjong Lee , Markus Klomfass

We present a lattice QCD determination of the b quark mass and of the B and B_s decay constants, performed with N_f=2 twisted mass Wilson fermions, by simulating at four values of the lattice spacing. In order to study the b quark on the…

We present results on the B-parameters $B_K$, $B^{3/2}_7$ and $B^{3/2}_8$, at $\beta=6.0$, with the tree-level Clover action. The renormalization of the complete basis of dimension-six four-fermion operators has been performed…

High Energy Physics - Lattice · Physics 2009-10-30 L. Conti , A. Donini , V. Gimenez , G. Martinelli , M. Talevi , A. Vladikas

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

We present results for the matrix elements of the additional $\Delta S=2$ operators that appear in models of physics beyond the Standard Model (BSM), expressed in terms of four BSM $B$-parameters. Combined with experimental results for…

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 one-loop matching coefficients between continuum and lattice QCD for the heavy-light four-fermion operators relevant for neutral B meson mixing both within and beyond the Standard Model. For the lattice theory we use…

High Energy Physics - Lattice · Physics 2008-11-26 Elvira Gamiz , Junko Shigemitsu , Howard Trottier

A lattice QCD calculation of the kaon $B$ parameter $B_K$ is carried out with the Wilson quark action in the quenched approximation at $\beta=6/g^2=5.9-6.5$. The mixing problem of the $\Delta s=2$ four-quark operators is solved…

High Energy Physics - Lattice · Physics 2009-10-31 S. Aoki , M. Fukugita , S. Hashimoto , N. Ishizuka , Y. Iwasaki , K. Kanaya , Y. Kuramashi , M. Okawa , A. Ukawa , T. Yoshie

We present results for the b \bar b spectrum obtained using an O(M_bv^6)-correct non-relativistic lattice QCD action. Propagators are evaluated on SESAM's three sets of dynamical gauge configurations generated with two flavours of Wilson…

High Energy Physics - Lattice · Physics 2009-10-30 A. Spitz , N. Eicker , J. Fingberg , S. Güsken , H. Hoeber , Th. Lippert , K. Schilling , J. Viehoff

We present a status report on simulations being done on $32^3 \times 64$ lattices at $\beta = 6.0$ using quenched Wilson fermions. Phenomenologically relevant results for the spectrum, decay constants, the kaon B-parameter $B_K$, $B_7$,…

High Energy Physics - Lattice · Physics 2010-05-27 Tanmoy Bhattacharya , Rajan Gupta

We describe how the Schroedinger functional and twisted mass QCD can be used to compute the kaon B-parameter B_K on the lattice with Wilson fermions. This new approach is expected to reduce the systematic uncertainties on B_K through a…

High Energy Physics - Lattice · Physics 2015-06-25 M. Guagnelli , J. Heitger , C. Pena , S. Sint , A. Vladikas
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