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Related papers: Automatic O$(a)$ improvement for twisted-mass QCD

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We show that maximally twisted mass fermions can be employed to regularize on the lattice the fully unquenched QCD+QED theory with vanishing $\theta$-term. We discuss how the critical mass of the up and down quarks can be conveniently…

High Energy Physics - Lattice · Physics 2016-12-08 Roberto Frezzotti , Giancarlo Rossi , Nazario Tantalo

Even highly improved variants of lattice QCD with staggered fermions show significant violations of taste symmetry at currently accessible lattice spacings. In addition, the "rooting trick" is used in order to simulate with the correct…

High Energy Physics - Lattice · Physics 2008-11-26 Claude Bernard , Maarten Golterman , Yigal Shamir

We present numerical results for the phase diagram of lattice QCD at finite temperature in the formulation with twisted mass Wilson fermions and a tree-level Symanzik-improved gauge action. Our simulations are performed on lattices with…

High Energy Physics - Lattice · Physics 2010-04-14 E. -M. Ilgenfritz , K. Jansen , M. P. Lombardo , M. Müller-Preußker , M. Petschlies , O. Philipsen , L. Zeidlewicz

We calculate analytically the improvement coefficients of the static axial and vector currents in O(a) improved lattice QCD at one-loop order of perturbation theory. The static quark is described by the hypercubic action, previously…

High Energy Physics - Lattice · Physics 2008-11-26 A. Grimbach , D. Guazzini , F. Knechtli , F. Palombi

In master-field simulations of lattice QCD, the expectation values of interest are obtained from a single or at most a few representative gauge-field configurations on very large lattices. If the light quarks are included, the generation of…

High Energy Physics - Lattice · Physics 2020-06-12 Anthony Francis , Patrick Fritzsch , Martin Lüscher , Antonio Rago

We study a three dimensional Z(3)-symmetric effective theory of high temperature QCD. The exact lattice-continuum relations, needed in order to perform lattice simulations with physical parameters, are computed to order O(a^0) in lattice…

High Energy Physics - Lattice · Physics 2009-04-14 Aleksi Kurkela

We discuss kinematical enhancements of cutoff effects at short and intermediate distances. Starting from a pedagogical example with periodic boundary conditions, we switch to the case of the Schroedinger Functional, where the theoretical…

High Energy Physics - Lattice · Physics 2009-03-04 Michele Della Morte , Rainer Sommer , Shinji Takeda

We present our preliminary results of the non-perturbative determination of the valence mass dependent coefficients $b_\mathrm{A}-b_\mathrm{P}$ and $b_\mathrm{m}$ as well as the ratio $Z_\mathrm{P} Z_\mathrm{m}/ Z_\mathrm{A}$ entering the…

High Energy Physics - Lattice · Physics 2017-10-20 Giulia Maria de Divitiis , Maurizio Firrotta , Jochen Heitger , Carl Christian Köster , Anastassios Vladikas

We calculate finite volume effects on the pion masses and decay constant in twisted mass lattice QCD (tmLQCD) at finite lattice spacing. We show that the lighter neutral pion in tmLQCD gives rise to finite volume effects that are…

High Energy Physics - Lattice · Physics 2014-11-20 Gilberto Colangelo , Urs Wenger , Jackson M. S. Wu

A systematic treatment of O(a)-improvement in lattice theories with static quarks is presented. The Schr\"odinger functional is discussed and a renormalization condition for the static axial current in the SF-scheme is introduced. Its…

High Energy Physics - Lattice · Physics 2015-06-25 Martin Kurth , Rainer Sommer

We show that the application of twisted mass QCD (tmQCD) with four (Wilson) quark flavours to the computation of lattice weak matrix elements relevant to $\Delta I=1/2$ transitions has important advantages: the renormalisation of $K \to…

High Energy Physics - Lattice · Physics 2009-11-07 C. Pena , S. Sint , A. Vladikas

We estimate the lattice artifacts in loop correction perturbatively for domain-wall QCD with infinite number of extra flavors. We find that there appear no ${\cal O}(a)$ errors in renormalization factors of quark wave function, mass and…

High Energy Physics - Lattice · Physics 2009-10-31 Junichi Noaki , Yusuke Taniguchi

We examine whether the $O(a)$ improved quark action on anisotropic lattices can be used as a framework for the heavy quark, which enables precision computation of matrix elements of heavy-light mesons. To this end, it is crucial to verify…

High Energy Physics - Lattice · Physics 2009-11-07 H. Matsufuru , J. Harada , T. Onogi , A. Sugita

We calculate charmed meson spectra and decay constants in lattice QCD employing one-loop $O(a)$ improved heavy quark action and axial-vector currents. In quenched simulations at $a \sim 0.1$ fm with the plaquette gauge action as well as a…

High Energy Physics - Lattice · Physics 2007-05-23 Y. Kayaba , S. Aoki , M. Fukugita , K-I. Ishikawa , Y. Iwasaki , K. Kanaya , T. Kaneko , Y. Kuramashi , M. Okawa , A. Ukawa , T. Yoshié

A general class of loop quantizations for anisotropic models is introduced and discussed, which enhances loop quantum cosmology by relevant features seen in inhomogeneous situations. The main new effect is an underlying lattice which is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Daniel Cartin , Gaurav Khanna

We perform a non-perturbative determination of the improvement coefficient c_A to remove O(a) discretization errors in the axial vector current in three-flavor lattice QCD with the Iwasaki gauge action and the standard O$(a)$-improved…

High Energy Physics - Lattice · Physics 2010-10-27 T. Kaneko , S. Aoki , M. Della Morte , S. Hashimoto , R. Hoffmann , R. Sommer

We determine non-perturbatively the normalisation constant Z_m*Z_P/Z_A as well as the Symanzik coefficients b_m and b_A-b_P, required in O(a) improved quark mass renormalisation with Wilson fermions. The strategy underlying their…

We report progress in our exploration of the finite-temperature phase structure of two-flavour lattice QCD with twisted-mass Wilson fermions and a tree-level Symanzik-improved gauge action for a temporal lattice size N_{\tau}=8. Extending…

High Energy Physics - Lattice · Physics 2010-01-21 E. -M. Ilgenfritz , K. Jansen , M. P. Lombardo , M. Müller-Preussker , M. Petschlies , O. Philipsen , L. Zeidlewicz

We explore how rotational invariance is systematically recovered from calculations on hyper-cubic lattices through the use of smeared lattice operators that smoothly evolve into continuum operators with definite angular momentum as the…

High Energy Physics - Lattice · Physics 2015-03-20 Zohreh Davoudi , Martin J. Savage

Using the O(a) Symanzik improved action an estimate is given for the strange quark mass for unquenched (n_f=2) QCD. The determination is via the axial Ward identity (AWI) and includes a non-perturbative evaluation of the renormalisation…

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