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Related papers: Partial twisting for scalar mesons

200 papers

We present a first scaling test of twisted mass QCD with pure Wilson quarks for a twisting angle of pi/2. We have computed the vector meson mass and the pseudoscalar decay constant for different values of beta at fixed value of r_0 m_PS.…

High Energy Physics - Lattice · Physics 2009-11-10 Karl Jansen , Andrea Shindler , Carsten Urbach , Ines Wetzorke

Quenched QCD simulations on three volumes, $8^3 \times$, $12^3 \times$ and $16^3 \times 32$ and three couplings, $\beta=5.7$, 5.85 and 6.0 using domain wall fermions provide a consistent picture of quenched QCD. We demonstrate that the…

In recent years there has been much progress on the investigation of the QCD phase diagram with lattice QCD. This talk will focus on the developments in the last few years. Especially the addition of external influences and extended ranges…

High Energy Physics - Lattice · Physics 2022-01-07 Jana N. Guenther

We describe a novel framework for partially quenched chiral perturbation theory based on the replica method. The computational rules are exceedingly simple. We illustrate these rules by computing the partially quenched chiral condensate to…

High Energy Physics - Lattice · Physics 2009-10-31 P. H. Damgaard , K. Splittorff

We present a scaling study of lattice QCD with O(a) improved Wilson fermions and a chirally twisted mass term. In order to get precise results with a moderate computational effort, we have considered a system of physical size of 0.75^3 *…

High Energy Physics - Lattice · Physics 2009-10-31 M. Della Morte , R. Frezzotti , J. Heitger , S. Sint

We study lattice QCD in the limit that the quark mass and chemical potential are simultaneously made large, resulting in a controllable density of quarks which do not move; this is similar in spirit to the quenched approximation for zero…

High Energy Physics - Lattice · Physics 2007-05-23 T. Blum , J. E. Hetrick , D. Toussaint

We study the possibility that the light scalar mesons are (qbar qbar q q) states rather than (qbar q). We perform a lattice QCD calculation of pseudoscalar meson scattering amplitudes, ignoring quark loops and quark annihilation, and find…

High Energy Physics - Lattice · Physics 2008-11-26 Mark Alford , R. L. Jaffe

We discuss quantum many-body systems with lattice translation and discrete onsite symmetries. We point out that, under a boundary condition twisted by a symmetry operation, there is an exact degeneracy of ground states if the unit cell…

Strongly Correlated Electrons · Physics 2021-06-02 Yuan Yao , Masaki Oshikawa

We point out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. The way in which this affects the lattice determination of weak matrix elements can be understood…

High Energy Physics - Lattice · Physics 2016-09-01 Maarten Golterman , Elisabetta Pallante

A brief overview of the lattice technique of studying QCD is presented. Recent results from the UKQCD Collaboration's simulations with dynamical quarks are then presented. In this work, the calculations are all at a fixed lattice spacing…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chris Allton

This is an exploratory study of the lightest non-singlet scalar $q\bar q$ state on the lattice with two dynamical quarks. Domain Wall fermions are used for both sea and valence quarks on a 16^3*32 lattice with an inverse lattice spacing of…

High Energy Physics - Lattice · Physics 2008-11-26 S. Prelovsek , C. Dawson , T. Izubuchi , K. Orginos , A. Soni

The phase structure of zero temperature twisted mass lattice QCD is investigated. We find strong metastabilities in the plaquette observable when the untwisted quark mass assumes positive or negative values. We provide interpretations of…

High Energy Physics - Lattice · Physics 2009-11-10 F. Farchioni , R. Frezzotti , K. Jansen , I. Montvay , G. C. Rossi , E. Scholz , A. Shindler , N. Ukita , C. Urbach , I. Wetzorke

We present a first numerical study of lattice QCD with O(a) improved Wilson quarks and a chirally twisted mass term. Renormalized correlation functions are derived from the Schroedinger functional and evaluated in an intermediate space-time…

High Energy Physics - Lattice · Physics 2010-02-03 M. Della Morte , R. Frezzotti , J. Heitger , S. Sint

We use vector flavor symmetry to relate form factors of isospin changing operators to isovector form factors. Flavor twisted boundary conditions in lattice QCD thus allow isovector form factors of twist-two operators, e.g, to be computed at…

High Energy Physics - Lattice · Physics 2009-11-11 Brian C. Tiburzi

Lattice QCD with Wilson quarks and a chirally twisted mass term represents a promising alternative regularization of QCD, which does not suffer from unphysical fermion zero modes. We show how the correlation functions of the renormalized…

High Energy Physics - Lattice · Physics 2010-02-03 Roberto Frezzotti , Pietro Antonio Grassi , Stefan Sint , Peter Weisz

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

We present one-loop results for the forward twist-two matrix elements relevant to the unpolarised, helicity and transversity baryon structure functions, in partially-quenched (N_f=2 and N_f=2+1) heavy baryon chiral perturbation theory. The…

High Energy Physics - Lattice · Physics 2008-11-26 William Detmold , C. -J. David Lin

In this paper we discuss how the peculiar properties of twisted lattice QCD at maximal twist can be employed to set up a consistent computational scheme in which, despite the explicit breaking of chiral symmetry induced by the presence of…

High Energy Physics - Lattice · Physics 2010-02-03 R. Frezzotti , G. C. Rossi

The curvature which characterizes the QCD phase transition at finite temperature and small values of the chemical potential is accessible to lattice simulations. The results for this quantity which have been obtained by several different…

High Energy Physics - Phenomenology · Physics 2011-04-20 Bertram Klein , Jens Braun , Bernd-Jochen Schaefer

We construct the Isgur-Wise limit of QCD in a form appropriate to lattice gauge theory techniques. The formulation permits a calculation of heavy quark processes even when the momentum transfers are much larger than the inverse lattice…

High Energy Physics - Lattice · Physics 2010-11-01 Jeffrey E. Mandula , Michael C. Ogilvie