English
Related papers

Related papers: BK-parameter from Nf = 2 twisted mass lattice QCD

200 papers

We calculate the $B \to\pi\ell\nu$ and $B_s \to K \ell\nu$ form factors in dynamical lattice QCD. We use the (2+1)-flavor RBC-UKQCD gauge-field ensembles generated with the domain-wall fermion and Iwasaki gauge actions. For the $b$ quarks…

High Energy Physics - Lattice · Physics 2015-04-28 J. M. Flynn , T. Izubuchi , T. Kawanai , C. Lehner , A. Soni , R. S. Van de Water , O. Witzel

We present a precise lattice QCD determination of the b-quark mass, of the B and Bs decay constants and first preliminary results for the B-mesons bag parameter. Simulations are performed with Nf = 2 Wilson twisted mass fermions at four…

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 present a preliminary lattice determination of the masses and decay constants of the pseudoscalar and vector mesons $B_c$ and $B_c^*$. Our analysis is based on the gauge configurations produced by the European Twisted Mass Collaboration…

High Energy Physics - Lattice · Physics 2018-12-04 D. Becirevic , A. Melis , L. Riggio , G. Salerno , S. Simula

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 light quark masses and the neutral kaon mixing parameter $B_K$ from lattice QCD. Our data set includes lighter than physical light quark masses and 5 lattice spacings so that chiral extrapolation is not necessary…

High Energy Physics - Phenomenology · Physics 2012-07-02 Christian Hoelbling

By combining the first unquenched lattice computation of the B-meson binding energy with the recently calculated two-loop contribution to the lattice HQET mass, we determine the $\bar{MS}$ b-quark mass, $\bar{m}_{b}(\bar{m}_{b})$ at the…

High Energy Physics - Lattice · Physics 2015-06-25 V. Gimenez , L. Giusti , F. Rapuano , G. Martinelli

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

The mass m_K* and vector coupling f_K* of the K*-meson, as well as the ratio of the tensor to vector couplings fT/fV|_K*, are computed in lattice QCD. Our simulations are performed in a partially quenched setup, with two dynamical (sea)…

High Energy Physics - Lattice · Physics 2011-08-09 P. Dimopoulos , F. Mescia , A. Vladikas

We determine hadronic matrix elements relevant for the mass and width differences, $\Delta M_s$ & $\Delta \Gamma_s$ in the $B^0_s - \bar{B^0_s}$ meson system using fully unquenched lattice QCD. We employ the MILC collaboration gauge…

We calculate non-perturbative renormalization factors at hadronic scale for $\Delta S=2$ four-quark operators in quenched domain-wall QCD using the Schr\"{o}dinger functional method. Combining them with the non-perturbative renormalization…

High Energy Physics - Lattice · Physics 2019-08-14 Yousuke Nakamura , Sinya Aoki , Yusuke Taniguchi , Tomoteru Yoshié

We present an exploratory lattice study of $B\to\pi$ semileptonic decay form factors using the nonrelativistic lattice QCD for heavy quark with Wilson light quark on a $16^3 \times 32$ quenched lattice at $\beta=5.8$. The matrix elements…

High Energy Physics - Lattice · Physics 2009-10-30 S. Hashimoto , K-I. Ishikawa , H. Matsufuru , T. Onogi , N. Yamada

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 an accurate lattice QCD computation of the b-quark mass, the B and Bs decay constants, the B-mixing bag-parameters for the full four-fermion operator basis, as well as estimates for \xi and f_{Bq}\sqrt{B_q} extrapolated to the…

We compute the b quark mass from dynamical lattice QCD with clover quarks. The calculation is done at a fixed lattice spacing with sea quark masses as low as half the strange quark mass. Our final result is m_b(m_b} = 4.25(2)(11) GeV, where…

High Energy Physics - Lattice · Physics 2008-11-26 UKQCD Collaboration , C. McNeile , C. Michael , Gavin Thompson

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 a calculation of the standard model \Delta S=2 matrix element relevant to indirect CP violation in K->\pi\pi decays which uses Neuberger's chiral formulation of lattice fermions. The computation is performed in the quenched…

High Energy Physics - Phenomenology · Physics 2009-11-10 Nicolas Garron , Leonardo Giusti , Christian Hoelbling , Laurent Lellouch , Claudio Rebbi

We extend our previous studies to calculate the B meson B parameters B_B and B_S on the lattice, and present an update of the results for the B_s meson width difference. We perform an extensive study of systematic errors in the quenched…

High Energy Physics - Phenomenology · Physics 2016-11-23 Shoji Hashimoto , Norikazu Yamada

Partially quenched Quantum Chromodynamics with Wilson fermions on a lattice is considered in the framework of chiral perturbation theory. Two degenerate quark flavours are associated with a chirally twisted mass term. The pion masses and…

High Energy Physics - Lattice · Physics 2010-12-17 Gernot Münster , Christian Schmidt , Enno E. Scholz

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