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Related papers: Unphysical Operators in Partially Quenched QCD

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It has been proposed that partially quenched chiral perturbation theory can be used together with partially quenched lattice QCD to determine the low-energy constants of real QCD. We point out a complication of this approach and show how it…

High Energy Physics - Lattice · Physics 2009-11-10 Stephen R. Sharpe , Ruth S. Van de Water

We calculate various properties of pseudoscalar mesons in partially quenched QCD using chiral perturbation theory through next-to-leading order. Our results can be used to extrapolate to QCD from partially quenched simulations, as long as…

High Energy Physics - Lattice · Physics 2009-10-31 Stephen Sharpe , Noam Shoresh

We develop chiral perturbation theory for baryons in quenched QCD. Quenching (the elimination of diagrams containing virtual quark loops) is achieved by extending the Lagrangian method of Bernard and Golterman, and is implemented in a…

High Energy Physics - Lattice · Physics 2009-10-28 James N. Labrenz , Stephen R. Sharpe

We apply different types of overlap operators in quenched QCD simulations to compute the zero mode contribution to the pseudo-scalar correlator. In particular we use the conventional Neuberger Dirac operator and the overlap hypercube Dirac…

High Energy Physics - Lattice · Physics 2007-05-23 S. Shcheredin , W. Bietenholz

We calculate the partition function of partially quenched chiral perturbation theory in the epsilon regime at next-to-leading order using the supersymmetry method in the formulation without a singlet particle. We include a nonzero imaginary…

High Energy Physics - Lattice · Physics 2009-11-30 Christoph Lehner , Tilo Wettig

Recently, we pointed out that chiral transformation properties of strong penguin operators change in the transition from unquenched to (partially) quenched QCD. As a consequence, new penguin-like operators appear in the (partially) quenched…

High Energy Physics - Lattice · Physics 2009-11-07 M. Golterman , E. Pallante

The standard QCD action is improved by the addition of irrelevant operators built with chiral composites. An effective Lagrangian is derived in terms of auxiliary fields, which has the form of the phenomenological chiral Lagrangians. Our…

High Energy Physics - Lattice · Physics 2007-05-23 Sergio Caracciolo , Fabrizio Palumbo , Roberto Scimia

We include the lowest-lying octet- and decuplet-baryons into partially quenched chiral perturbation theory. Perturbing about the chiral limit of the graded SU(6|3)_L x SU(6|3)_R flavor group of partially quenched QCD, we compute the leading…

High Energy Physics - Lattice · Physics 2008-11-26 Jiunn-Wei Chen , Martin J. Savage

The transformation properties of strong penguin operators under the action of the flavor group change when they are considered as operators in (partially) quenched QCD instead of the unquenched theory. An ambiguity arises, which is…

High Energy Physics - Lattice · Physics 2008-11-26 Maarten Golterman , Elisabetta Pallante

The transformation properties of strong penguin operators under the action of the flavor group change when they are considered as operators in (partially) quenched QCD instead of the unquenched theory. As a result, additional operators and…

High Energy Physics - Lattice · Physics 2009-11-11 M. Golterman , E. Pallante

Strong penguin operators are singlets under the right-handed flavor symmetry group SU(3)_R. However, they do not remain singlets when the operator is embedded in (partially) quenched QCD, but instead they become linear combinations of two…

High Energy Physics - Lattice · Physics 2008-11-26 Maarten Golterman , Santi Peris

I discuss the properties of pions in ``partially quenched'' theories, i.e. those in which the valence and sea quark masses, $m_V$ and $m_S$, are different. I point out that for lattice fermions which retain some chiral symmetry on the…

High Energy Physics - Lattice · Physics 2014-11-17 Stephen R. Sharpe

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

[This version is a minor revision of a previously submitted preprint. Only references have been changed.] We describe a technique for constructing the effective chiral theory for quenched QCD. The effective theory which results is a…

High Energy Physics - Lattice · Physics 2009-10-22 Claude Bernard , Maarten Golterman

We study taste and Euclidean rotational symmetry violation for staggered fermions at nonzero lattice spacing using staggered chiral perturbation theory. We extend the staggered chiral Lagrangian to O(a^2 p^2), O(a^4) and O(a^2 m), the…

High Energy Physics - Lattice · Physics 2010-11-19 Stephen R. Sharpe , Ruth S. Van de Water

The vector meson mass is extracted from a large sample of partially quenched, two-flavor lattice QCD simulations. For the first time, discretisation, finite-volume and partial quenching artefacts are treated in a unified framework which is…

High Energy Physics - Lattice · Physics 2010-02-17 C. R. Allton , W. Armour , D. B. Leinweber , A. W. Thomas , R. D. Young

We consider the low energy effective action of QCD below the chiral symmetry breaking scale, including, in Wilson's spirit, all operators of dimensionality less or equal to 6 which can be built with quark and chiral fields. The effect of…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. A. Andrianov , D. Espriu , R. Tarrach

The chiral nonanalytic behaviour of quark-flavor contributions to the magnetic moments of octet baryons are determined in full, quenched and partially-quenched QCD, using an intuitive and efficient diagrammatic formulation of quenched and…

High Energy Physics - Lattice · Physics 2011-07-19 Derek B. Leinweber

Baryons of lower spin in partially quenched large-$N_c$ QCD are studied with particular emphasis to interpolation between standard unquenched and fully quenched limits. In large $N_c$ limit of partially quenched QCD, we calculate $\Delta…

High Energy Physics - Phenomenology · Physics 2007-05-23 Chi-Keung Chow , Soo-Jong Rey

We discuss the importance of using partially quenched theories with three degenerate quarks for extrapolating to QCD, and present some relevant results from chiral perturbation theory.

High Energy Physics - Lattice · Physics 2015-06-25 S. Sharpe , N. Shoresh
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