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Related papers: Determination of $\Lambda_{\overline{MS}}$ from qu…

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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 an update on our previous determination of the Lambda parameter in QCD. The main emphasis is on results for two flavours of light dynamical quarks, where we can now almost double the amount of data used, including values at…

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

We compute $\Lambda_{\bar{MS}}$ for two flavors of light dynamical quarks using non-perturbatively $O(a)$ improved Wilson fermions. We improve on a recent calculation by employing Pad\'e-improved two-loop and three-loop perturbation theory…

High Energy Physics - Lattice · Physics 2008-11-26 S. Booth , M. Göckeler , R. Horsley , A. C. Irving , B. Joo , S. Pickles , D. Pleiter , P. E. L. Rakow , G. Schierholz , Z. Sroczynski , H. Stüben

While lattice QCD allows for reliable results at small momentum transfers (large quark separations), perturbative QCD is restricted to large momentum transfers (small quark separations). The latter is determined up to a reference momentum…

High Energy Physics - Phenomenology · Physics 2018-12-18 Felix Karbstein , Marc Wagner , Michelle Weber

We determine $\Lambda_{\bar{\textrm{MS}}}^{(n_f=2)}$ by fitting perturbative expressions for the quark-antiquark static potential to lattice results for QCD with $n_f=2$ dynamical quark flavors. To this end we use the perturbative static…

High Energy Physics - Phenomenology · Physics 2014-10-01 Felix Karbstein , Antje Peters , Marc Wagner

A completely non-perturbative estimate is given for the u/d and strange quark masses in quenched QCD using O(a) improved fermions and, for comparison, Wilson fermions. For improved fermions we find m_{u/d}^MSbar(\mu=2 GeV) = 4.4(2) MeV,…

High Energy Physics - Lattice · Physics 2015-06-25 M. Gockeler , R. Horsley , B. Klaus , W. Kurzinger , H. Oelrich , D. Petters , D. Pleiter , P. E. L. Rakow , G. Schierholz , P. Stephenson

We determine Lambda_msbar for QCD with n_f=2 dynamical quark flavors by fitting the Q-Q-bar static potential known analytically in the perturbative regime up to terms of O(alpha_s^4) and ~alpha_s^4 ln(alpha_s) to corresponding results…

High Energy Physics - Phenomenology · Physics 2012-02-16 ETM Collaboration , Karl Jansen , Felix Karbstein , Attila Nagy , Marc Wagner

We present preliminary results on the computation of the QCD running coupling constant in the MOM_tilde scheme and Landau gauge with two flavours of dynamical Wilson quarks. Gluon momenta range up to about 7 GeV (beta=5.6, 5.8 and 6.0) with…

High Energy Physics - Phenomenology · Physics 2010-03-19 Ph. Boucaud , J. P. Leroy , J. Micheli , H. Moutarde , O. Pene , J. Rodriguez-Quintero , C. Roiesnel

We compute the strange and the average up/down quark masses in the quenched approximation of lattice QCD, by using the O(a)-improved Wilson action and operators and by implementing the non-perturbative renormalization. Our computation is…

High Energy Physics - Lattice · Physics 2008-11-26 Damir Becirevic , Vittorio Lubicz , Cecilia Tarantino

We present the results of a partially quenched lattice QCD calculation of light quark masses with $N_f=2$ degenerate dynamical flavors. Numerical simulations are carried out using the plaquette gauge action and the Wilson quark action at…

High Energy Physics - Lattice · Physics 2010-03-19 D. Becirevic , B. Blossier , Ph. Boucaud , V. Gimenez , V. Lubicz , F. Mescia , S. Simula , C. Tarantino

We present results of a numerical calculation of lattice QCD with two degenerate flavors of dynamical quarks, identified with up and down quarks, and with a strange quark treated in the quenched approximation. The lattice action and…

We use the recently obtained theoretical expression for the complete QCD static energy at next-to-next-to-next-to leading-logarithmic accuracy to determine r_0Lambda_MS by comparison with available lattice data, where r_0 is the lattice…

High Energy Physics - Phenomenology · Physics 2012-06-28 Nora Brambilla , Xavier Garcia i Tormo , Joan Soto , Antonio Vairo

We present estimates of the masses of light quarks using lattice data. Our main results are based on a global analysis of all the published data for Wilson, Sheikholeslami-Wohlert (clover), and staggered fermions, both in the quenched…

High Energy Physics - Lattice · Physics 2008-11-26 Rajan Gupta , Tanmoy Bhattacharya

We present numerical simulation of QCD with two dynamical quark flavors described by the overlap fermion action on a $16^3\times 32\times (0.12 {\rm fm})^4$ lattice. We calculate pseudo-scalar masses and decay constants and investigate…

High Energy Physics - Lattice · Physics 2009-04-14 J. Noaki , S. Aoki , H. Fukaya , S. Hashimoto , T. Kaneko , H. Matsufuru , T. Onogi , E. Shintani , N. Yamada

We explain how scale dependent renormalized quantities can be computed using lattice QCD. Two examples are used: the running coupling and quark masses. A reliable computation of the $\Lambda$-parameter in the quenched approximation is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Rainer Sommer

We compute the decay constants for the heavy--light pseudoscalar mesons in the quenched approximation and continuum limit of lattice QCD. Within the Schrodinger Functional framework, we make use of the step scaling method, which has been…

High Energy Physics - Lattice · Physics 2015-06-25 G. M. de Divitiis , M. Guagnelli , F. Palombi , R. Petronzio , N. Tantalo

We present estimates of light quarks masses using lattice data. Our main results are based on a global analysis of all the published data for Wilson and Staggered fermions, both in the quenched approximation and with $n_f=2$ dynamical…

High Energy Physics - Lattice · Physics 2016-09-01 R. Gupta , T. Bhattacharya

A recent lattice calculation of the QCD running coupling is presented. The coupling is extracted from the force between two static quarks in the framework of the valence quark approximation. A value of the Lambda-parameter for zero quark…

High Energy Physics - Lattice · Physics 2009-09-25 Gunnar S. Bali

We present a determination of the strange quark mass for two flavours (nf=2) of light dynamical quarks using the axial Ward identity. The calculations are performed on the lattice using O(a) improved Wilson fermions and include a fully…

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

We present a high statistics study of the light hadron spectrum and quark masses in QCD with two flavors of dynamical quarks. Numerical simulations are carried out using the plaquette gauge action and the O(a)-improved Wilson quark action…

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