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Related papers: Quenched QCD near the chiral limit

200 papers

The quark mass dependence of meson masses and decay constants in N_f=2 QCD is studied at a fixed gauge coupling with different dynamical quark masses. Partially Quenched Wilson Chiral Perturbation Theory (PQWchiPT) is applied to obtain the…

High Energy Physics - Lattice · Physics 2009-11-10 q Collaboration , F. Farchioni , I. Montvay , E. Scholz

We present the recent Fermilab calculations of the masses of the light quarks, using tadpole-improved Sheikholeslami-Wohlert (SW) quarks. Various sources of systematic errors are studied. Our final result for the average light quark mass in…

High Energy Physics - Lattice · Physics 2010-11-19 T. Onogi , A. X. El-Khadra , B. J. Gough , G. M. Hockney , A. S. Kronfeld , P. B. Mackenzie , B. P. Mertens , J. N. Simone

The electromagnetic properties of baryons containing a heavy quark are calculated at next-to-leading order in partially quenched heavy hadron chiral perturbation theory. Calculations are performed for three light flavors in the isospin…

High Energy Physics - Lattice · Physics 2009-11-10 Brian C. Tiburzi

We present the first investigation of the extrapolation of quenched nucleon magnetic moments in quenched chiral effective field theory. We utilize established techniques in finite-range regularisation and compare with standard dimensional…

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

Several topics concerning the light hadron spectrum are discussed. Flavor symmetry breaking effects and the problem of quenched chiral logarithm are examined with pion mass data for the Kogut-Susskind quark action, and light meson decay…

High Energy Physics - Lattice · Physics 2009-10-28 JLQCD Collaboration , S. Aoki , M. Fukugita , S. Hashimoto , N. Ishizuka , Y. Iwasaki , K. Kanaya , Y. Kuramashi , H. Mino , M. Okawa , A. Ukawa , T. Yoshie

We propose a general method to obtain accurate estimates for some of the "low-energy constants" in the one-loop effective chiral Lagrangian by means of simulating lattice QCD. In particular, the method is sensitive to those constants whose…

High Energy Physics - Lattice · Physics 2011-02-01 Jochen Heitger , Rainer Sommer , Hartmut Wittig

We review several results that have been obtained using lattice QCD with the staggered quark formulation. Our focus is on the quantities that have been calculated numerically with low statistical errors and have been extrapolated to the…

High Energy Physics - Lattice · Physics 2008-11-26 C. Aubin

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…

We calculate one-loop correction to the axial charges of the octet baryons using quenched chiral perturbation theory, in order to understand chiral behavior of the axial charges in quenched approximation to quantum chromodynamics (QCD). In…

High Energy Physics - Lattice · Physics 2009-10-28 Myunggyu Kim , Seyong Kim

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 2009-10-28 Thomas C. Blum , James E. Hetrick , Doug Toussaint

The divergences of the generating functional of quenched Chiral Perturbation theory (qCHPT) to one loop are computed in closed form. We show how the quenched chiral logarithms can be reabsorbed in the renormalization of the $B_0$ parameter…

High Energy Physics - Lattice · Physics 2009-10-30 G. Colangelo , E. Pallante

We present an update of the MILC studies of the physics of light pseudoscalars using improved staggered fermions. New runs at lighter quark mass, as well as increased statistics for older sets, are enabling us to improve the results for…

We present results for physical quantities computed in quenched chiral perturbation theory and compare them with the corresponding unquenched expressions. We also point out an apparent theoretical problem of the quenched approximation.…

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

We investigate the use of two types of non-local (``smeared'') sources for quark propagators in quenched lattice QCD at $\beta=6.0$ using Wilson fermions at $\kappa=0.154$ and $0.155$. We present results for the hadron mass spectrum, meson…

High Energy Physics - Lattice · Physics 2014-11-17 D. Daniel , R. Gupta , G. Kilcup , A. Patel , S. Sharpe

Simulations that use the clover action in quenched QCD calculations have a lower limit to the quark mass that can be reached, because of the fluctuations caused by exceptional configurations. From this low statistics study, we find that the…

High Energy Physics - Lattice · Physics 2008-11-26 UKQCD collaboration , Craig McNeile , Chris Michael

We present results for masses of excited mesons from quenched calculations using chirally improved quarks at pion masses down to 350 MeV. The key features of our analysis are the use of a matrix of correlators from various source and sink…

High Energy Physics - Lattice · Physics 2009-11-11 Tommy Burch , Christof Gattringer , Leonid Ya. Glozman , Christian Hagen , C. B. Lang , Andreas Schäfer

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

Finite-range regularised (FRR) chiral effective field theory is presented in the context of approximation schemes ubiquitous in modern lattice QCD calculations. Using FRR techniques, the power-counting regime (PCR) of chiral perturbation…

High Energy Physics - Lattice · Physics 2010-02-17 Derek B. Leinweber , Anthony W. Thomas , Ross D. Young

Using a chiral random matrix theory we can now derive the low energy partition functions and Dirac eigenvalue correlations of QCD with different chemical potentials for the dynamical and valence quarks. The results can also be extended to…

High Energy Physics - Lattice · Physics 2008-11-26 James C. Osborn

Some new results on nonperturbative renormalisation of quark bilinears in quenched QCD with Schroedinger Functional techniques are presented. Special emphasis is put on a study of the universality of the continuum limit for step scaling…

High Energy Physics - Lattice · Physics 2015-06-25 M. Guagnelli , J. Heitger , C. Pena , A. Vladikas