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Related papers: $O(a)$ Improvement of Nucleon Matrix Elements

200 papers

We propose a non-perturbative method for computing the renormalization constants of generic composite operators. This method is intended to reduce some systematic errors, which are present when one tries to obtain physical predictions from…

High Energy Physics - Lattice · Physics 2009-10-09 G. Martinelli , C. Pittori , C. T. Sachrajda , M. Testa , A. Vladikas

We present results of a lattice computation of the matrix elements of the vector and axial-vector currents which are relevant for the semi-leptonic decays $D \rightarrow K$ and $D \rightarrow K^*$. The computations are performed in the…

High Energy Physics - Lattice · Physics 2009-10-28 Juan M. Nieves

Recently the asymptotic lattice spacing dependence of spectral quantities in lattice QCD has been computed to $\mathrm{O}(a^2)$ using Symanzik Effective theory [1,2]. Here, we extend these results to matrix elements and correlators of local…

High Energy Physics - Lattice · Physics 2024-09-04 Nikolai Husung

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

We consider O(a) improvement for two flavor lattice QCD. The improvement term in the action is computed non-perturbatively for a large range of the bare coupling. The position of the critical line and higher order lattice artifacts…

High Energy Physics - Lattice · Physics 2009-10-31 Karl Jansen , Rainer Sommer

We present state-of-the-art results from a lattice QCD calculation of the nucleon axial coupling, $g_A$, using M\"obius Domain-Wall fermions solved on the dynamical $N_f = 2 + 1 + 1$ HISQ ensembles after they are smeared using the…

Lattice simulations of QCD have produced precise estimates for the masses of the lowest-lying hadrons which show excellent agreement with experiment. By contrast, lattice results for the vector and axial vector form factors of the nucleon…

High Energy Physics - Lattice · Physics 2011-09-23 B. B. Brandt , S. Capitani , M. Della Morte , D. Djukanovic , J. Gegelia , G. von Hippel , A. Juttner , B. Knippschild , H. B. Meyer , H. Wittig

We present preliminary results for B_K, B_7^{3/2} and B_8^{3/2} from two high-statistics lattice computations. These calculations are performed at beta=6.0 and 6.2 in the quenched approximation, using mean-field-improved…

High Energy Physics - Lattice · Physics 2008-11-26 Laurent Lellouch , C. -J. David Lin , UKQCD Collaboration

We study the performance of all-mode-averaging (AMA) when used in conjunction with a locally deflated SAP-preconditioned solver, determining how to optimize the local block sizes and number of deflation fields in order to minimize the…

High Energy Physics - Lattice · Physics 2016-11-21 Georg von Hippel , Thomas D. Rae , Eigo Shintani , Hartmut Wittig

We present results at beta=6.0 and 6.2 for the O(a) improvement and renormalization constants for bilinear operators using axial and vector Ward identities. We discuss the extraction of the mass dependence of the renormalization constants…

High Energy Physics - Lattice · Physics 2010-05-27 Tanmoy Bhattacharya , Rajan Gupta , Weonjong Lee , Stephen Sharpe

As algorithms and computing power have advanced, lattice QCD has become a precision technique for many QCD observables. However, the calculation of nucleon matrix elements remains an open challenge. I summarize the status of the lattice…

High Energy Physics - Lattice · Physics 2015-05-27 Dru B. Renner

We investigate higher order effects in the nonrelativistic expansion of lattice QCD on the heavy-light meson decay constants and some other quantities in order to understand the truncation error of NRQCD. While our numerical results have…

High Energy Physics - Lattice · Physics 2011-01-27 N. Yamada , S. Hashimoto , K-I. Ishikawa , H. Matsufuru , T. Onogi

We have gained enough statistical precision to distinguish signal from noise in matrix elements of all operators relevant for the Delta I=1/2 rule in kaon decays and for the direct CP violation parameter epsilon-prime. We confirm…

High Energy Physics - Lattice · Physics 2007-05-23 D. Pekurovsky , G. Kilcup

Accurate measurements of K, D and B meson mixing amplitudes provide stringent constraints in the Unitary Triangle analysis, as well as useful bounds on New Physics scales. Lattice QCD provides a non perturbative tool to compute the hadronic…

High Energy Physics - Lattice · Physics 2014-11-11 Nuria Carrasco

Neutrinoless double-beta ($0\nu\beta\beta$) decays provide an excellent probe for determining whether neutrinos are Dirac or Majorana fermions. The short-range matrix elements associated with the $\pi^- \to \pi^+ ee$ process contribute at…

The coefficients multiplying the counterterms required for O($a$) improvement of the action and the isovector axial current in lattice QCD are computed non-perturbatively, in the quenched approximation and for bare gauge couplings $g_0$ in…

High Energy Physics - Lattice · Physics 2016-09-01 Martin Luescher , Stefan Sint , Rainer Sommer , Peter Weisz , Ulli Wolff

We present preliminary results of the first lattice QCD calculation of the K -> pi matrix elements of the chromomagnetic operator O_{CM}=g sbar sigma_{munu} G_{munu} d, which appears in the effective Hamiltonian describing Delta S=1…

High Energy Physics - Lattice · Physics 2015-09-02 M. Constantinou , M. Costa , R. Frezzotti , V. Lubicz , G. Martinelli , D. Meloni , H. Panagopoulos , S. Simula

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 present the complete 1-loop perturbative computation of the renormalization constants and mixing coefficients of the operators that measure the first moment of deep inelastic scattering structure functions, employing the nearest neighbor…

High Energy Physics - Lattice · Physics 2009-10-22 Stefano Capitani , Giancarlo Rossi

We compute logarithmic corrections to the O(a^2) lattice artifacts for a class of lattice actions for the non-linear O(n) sigma-model in two dimensions. The generic leading artifacts are of the form $a^2[\ln(a^2)]^{(n/(n-2))}$. We also…

High Energy Physics - Lattice · Physics 2009-05-29 Janos Balog , Ferenc Niedermayer , Peter Weisz