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Related papers: Unphysical Operators in Partially Quenched QCD

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We extend a technique for the chiral extrapolation of hadron masses calculated with dynamical fermions to those generated by quenched simulations. The method ensures the correct leading and next-to-leading non-analytic behaviour for either…

High Energy Physics - Lattice · Physics 2007-05-23 R. D. Young , D. B. Leinweber , A. W. Thomas , S. V. Wright

In this contribution we present results from quenched QCD simulations with the parameterized fixed-point (FP) and the chirally improved (CI) Dirac operator. Both these operators are approximate solutions of the Ginsparg-Wilson equation and…

When we embed the strong penguin operator Q_6 in the quenched theory, it does not remain a singlet under right-handed chiral transformations. As a consequence, more low-energy constants associated with this operator appear than in the…

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

Partially quenched theories are theories in which the valence- and sea-quark masses are different. In this paper we calculate the nonanalytic one-loop corrections of some physical quantities: the chiral condensate, weak decay constants,…

High Energy Physics - Lattice · Physics 2008-11-26 Maarten Golterman , Ka Chun Leung

A new intuitive method for the rapid calculation of the leading nonanalytic behavior of hadronic observables in quenched chiral perturbation theory is presented. After proving the technique in a consideration of baryon masses, the quenched…

High Energy Physics - Lattice · Physics 2009-11-07 Derek B. Leinweber

The spectral density of euclidean Dirac operator is investigated in partially quenched QCD with arbitrary quark masses. A representation of scalar and pseudoscalar correlators in terms of the spectral density is discussed. The spectral…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. Zyablyuk

We consider in details the dual models for the Goldstone mesons (pions) scattering in the presence of the explicit chiral symmetry breaking caused by non-zero current quark mass. New method of incorporation of the quark masses into the dual…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. V. Polyakov , G. Weidl

The mass spectrum of the lowest lying octet baryons is calculated to next-to-next-to-leading order in heavy baryon chiral perturbation theory and partially quenched heavy baryon chiral perturbation theory. We work in the isospin limit and…

High Energy Physics - Lattice · Physics 2009-11-10 Andre Walker-Loud

We formally derive the chiral Lagrangian for low lying pseudoscalar mesons from the first principles of QCD considering the contributions from the normal part of the theory without taking approximations. The derivation is based on the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Qing Wang , Yu-Ping Kuang , Xue-Lei Wang , Ming Xiao

Quenched chiral perturbation is used to study the decay constants for heavy-light mesons beyond the leading order in 1/M. The results are used to estimate the error in quenched lattice calculations of the decay constants. For the double…

High Energy Physics - Phenomenology · Physics 2008-02-03 Michael J. Booth

A previously-proposed method of constructing spatially-extended gauge-invariant three-quark operators for use in Monte Carlo lattice QCD calculations is tested, and a methodology for using these operators to extract the energies of a large…

High Energy Physics - Lattice · Physics 2007-05-23 Adam C. Lichtl

A summary of recent progress in Chiral Perturbation Theory (ChPT) at the two-loop level is given. A short introduction to ChPT is included, along with an explanation of the usefulness of developing ChPT for partially quenched QCD. Further,…

High Energy Physics - Phenomenology · Physics 2008-11-26 Johan Bijnens , Niclas Danielsson , Timo A. Lahde

A pseudo-Goldstone boson for {\it quintessence} is known to require the decay constant $F_q\sim M_P$ and the height of the potential $(0.003 {\rm eV})^4$, and hence the pseudo-Goldstone boson mass of order $10^{-33}$ eV. The model-dependent…

High Energy Physics - Phenomenology · Physics 2014-11-17 Jihn E. Kim

We present updated results on chiral phase structure in (2+1)-flavor ($N_f$=2+1) and 3-flavor ($N_f=3$) QCD based on the simulations using Highly Improved Staggered Quarks on lattices with temporal extent $N_\tau$ =6 at vanishing baryon…

High Energy Physics - Lattice · Physics 2019-08-14 Heng-Tong Ding , Prasad Hegde

The construction of the first baryon operators for staggered lattice QCD exploited the taste symmetry to emulate physical quark flavor; contemporary 2+1 flavor simulations explicitly include three physical quark flavors and necessitate…

High Energy Physics - Lattice · Physics 2008-11-26 Jon A. Bailey

We develop quenched chiral perturbation theory for baryons using the graded-symmetry formalism of Bernard and Golterman and calculate non-analytic contributions to the baryon masses coming from quenched chiral loops. The usual term…

High Energy Physics - Lattice · Physics 2009-10-22 James N. Labrenz , Stephen R. Sharpe

We calculate the next-to-leading order axial current decay constants of taste non-Goldstone pions and kaons in staggered chiral perturbation theory. This is an extension of the taste Goldstone decay constants calculation to that of the…

High Energy Physics - Lattice · Physics 2013-01-16 Jon A. Bailey , Boram Yoon , Weonjong Lee

We extend the chiral Lagrangian with heavy quark-diquark symmetry to quenched and partially quenched theories. These theories are used to derive formulae for the chiral extrapolation of masses and hyperfine splittings of doubly heavy…

High Energy Physics - Lattice · Physics 2014-11-17 Thomas Mehen , Brian C. Tiburzi

The delta-regime of QCD is characterised by light quarks in a small spatial box, but a large extent in (Euclidean) time. In this setting a specific variant of chiral perturbation theory - the delta-expansion - applies, based on a quantum…

High Energy Physics - Lattice · Physics 2015-05-27 W. Bietenholz , N. Cundy , M. Gockeler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , G. Schierholz , J. M. Zanotti

We investigate two-point correlation functions of left-handed currents computed in quenched lattice QCD with the Neuberger-Dirac operator. We consider two lattice spacings a~0.09,0.12 fm and two different lattice extents L~ 1.5, 2.0 fm;…

High Energy Physics - Lattice · Physics 2010-02-03 L. Giusti , P. Hernandez , S. Necco , C. Pena , J. Wennekers , H. Wittig