English
Related papers

Related papers: Some remarks on O(a) improved twisted mass QCD

200 papers

Twisted mass fermions allow light quarks to be explored but with the consequence that there are mass splittings, such as between the neutral and charged pion. Using a direct calculation of the connected neutral pion correlator and…

It is shown how on-shell O(a) improvement can be implemented non-perturbatively in lattice QCD with Wilson quarks. Improvement conditions are obtained by requiring the PCAC relation to hold exactly in certain matrix elements. These are…

High Energy Physics - Lattice · Physics 2009-10-28 M. Lüscher , S. Sint , R. Sommer , P. Weisz , H. Wittig , U. Wolff

QCD in two dimensions is investigated using the improved fermionic lattice Hamiltonian proposed by Luo, Chen, Xu, and Jiang. We show that the improved theory leads to a significant reduction of the finite lattice spacing errors. The quark…

High Energy Physics - Lattice · Physics 2016-08-15 Jun-Qin Jiang , Xiang-Qian Luo , Zhong-Hao Mei , Hamza Jirari , Helmut Kröger , Chi-Min Wu

We investigate the thermal QCD phase transition and its scaling properties on the lattice. The simulations are performed with $N_f=2+1+1$ Wilson twisted mass fermions at pion masses from physical up to heavy quark regime. We introduce a…

High Energy Physics - Lattice · Physics 2022-04-12 A. Yu. Kotov , M. P. Lombardo , A. Trunin

We have explored twisted mass LQCD (tmLQCD) analytically using chiral perturbation theory, including discretization effects up to O(a^2), and working at next-to-leading (NLO) order in the chiral expansion. In particular we have studied the…

High Energy Physics - Lattice · Physics 2009-11-10 Stephen R. Sharpe , Jackson M. S. Wu

I report on the application of tmQCD techniques to the computation of hadronic matrix elements of four-fermion operators. Emphasis is put on the computation of $B_K$ in quenched QCD performed by the ALPHA Collaboration. The extension of…

High Energy Physics - Lattice · Physics 2009-09-29 Carlos Pena

We consider spectral quantities in lattice QCD and determine the asymptotic behavior of their discretization errors. Wilson fermion with O$(a)$-improvement, (M\"obius) Domain wall fermion (DWF), and overlap Dirac operators are considered in…

High Energy Physics - Lattice · Physics 2024-10-18 Nikolai Husung , Peter Marquard , Rainer Sommer

We compute the hadron mass spectrum, the quark masses and the meson decay constants in quenched lattice QCD with non-perturbatively $O(a)$ improved Wilson fermions. The calculations are done for two values of the coupling constant, $\beta =…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , H. Perlt , P. Rakow , G. Schierholz , A. Schiller , P. Stephenson

In the framework of Wilson Chiral Perturbation Theory, we study the effect induced by a twisted Wilson term, as it appears in Twisted Mass QCD (with 2 degenerate quarks). In particular we consider the vacuum orientation and the pion masses.…

High Energy Physics - Lattice · Physics 2009-11-10 Luigi Scorzato

We present the current status of a revised strategy to compute the running of renormalized quark masses in QCD with three flavours of massless O(a) improved Wilson quarks. The strategy employed uses the standard finite-size scaling method…

High Energy Physics - Lattice · Physics 2015-08-28 I. Campos , P. Fritzsch , C. Pena , D. Preti , A. Ramos , A. Vladikas

We investigate the thermal QCD transition with two flavors of maximally twisted mass fermions for a set of pion masses, 300 MeV \textless $m_\pi$ \textless 500 MeV, and lattice spacings $a$ \textless 0.09 fm. We determine the…

High Energy Physics - Lattice · Physics 2013-05-15 F. Burger , E. -M. Ilgenfritz , M. Kirchner , M. P. Lombardo , M. Muller-Preussker , O. Philipsen , C. Pinke , C. Urbach , L. Zeidlewicz

We discuss a mixed-action approach in which sea quarks are regularised using non-perturbatively ${\rm O}(a)$ improved Wilson fermions, while a fully-twisted tmQCD action is used for valence quarks. In this setup, automatic ${\rm O}(a)$…

High Energy Physics - Lattice · Physics 2018-04-18 Gregorio Herdoíza , Carlos Pena , David Preti , José Ángel Romero , Javier Ugarrio

We have investigated QCD with two flavors of degenerate fermions using a Symanzik-improved lattice action for both the gauge and fermion actions. Our study focuses on the deconfinement transition on an $N_t=4$ lattice. Having located the…

The introduction of a chirally twisted mass term has been proposed as an attractive approach to O(a) improvement of Quantum Chromodynamics with Wilson fermions on a lattice. For numerical simulation projects it is important to know the…

High Energy Physics - Lattice · Physics 2010-12-23 Gernot Münster

It has been shown that in the twisted mass formulation of Lattice QCD at maximal twist large cutoff effects are generated when the quark mass becomes of O(a Lambda_QCD^2). In general, these effects can be suppressed in two ways: either by…

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

I review recent theoretical developments and numerical results of twisted mass QCD. I argue that, combined with an efficient algorithm, twisted mass QCD can be an attractive QCD lattice action, to perform large scale simulations at small…

High Energy Physics - Lattice · Physics 2007-05-23 Andrea Shindler

QCD is investigated at finite temperature using Wilson fermions in the fixed scale approach. A 2+1 flavor stout and clover improved action is used at four lattice spacings allowing for control over discretization errors. The light quark…

We point out a caveat in the proof for automatic O(a) improvement in twisted mass lattice QCD at maximal twist angle. With the definition for the twist angle previously given by Frezzotti and Rossi, automatic O(a) improvement can fail…

High Energy Physics - Lattice · Physics 2009-11-10 Sinya Aoki , Oliver Baer

We study the scaling properties of the finite temperature QCD phase transition, for light quark masses ranging from the heavy quark regime to their physical values. The lattice results are obtained in the fixed scale approach from…

High Energy Physics - Lattice · Physics 2021-11-03 A. Yu. Kotov , M. P. Lombardo , A. Trunin

We present our progress in the non-perturbative O(a) improvement and renormalization of tensor currents in three-flavor lattice QCD with Wilson-clover fermions and tree-level Symanzik improved gauge action. The mass-independent O(a)…

High Energy Physics - Lattice · Physics 2019-10-16 Leonardo Chimirri , Patrick Fritzsch , Jochen Heitger , Fabian Joswig , Marco Panero , Carlos Pena , David Preti