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Related papers: Quenched QCD near the chiral limit

200 papers

I summarize recent progress in lattice gauge theory, with particular emphasis on results from numerical simulations. A major success has been the determination of the light hadron spectrum in the quenched approximation with sufficient…

High Energy Physics - Lattice · Physics 2007-05-23 Stephen R. Sharpe

Values for the strange quark mass and average up/down mass have been obtained from quenched lattice QCD simulations using the domain wall fermion action. This discretization preserves the properties of flavor and chiral symmetry at nonzero…

High Energy Physics - Lattice · Physics 2009-10-31 Matthew Wingate

We use a random matrix model to study chiral symmetry breaking in QCD at finite chemical potential $\mu$. We solve the model and compute the eigenvalue density of the Dirac matrix on a complex plane. A naive ``replica trick'' fails for…

High Energy Physics - Lattice · Physics 2009-10-28 M. A. Stephanov

These lectures describe the use of effective field theories to extrapolate results from the parameter region where numerical simulations of lattice QCD are possible to the physical parameters (physical quark masses, infinite volume,…

High Energy Physics - Lattice · Physics 2007-05-23 Stephen. R. Sharpe

Previous work at $6/g^2=5.7$ with quenched staggered quarks is extended with new calculations at 5.85 and 6.15 on lattices up to $32^3\times 64$. These calculations allow a more detailed study of extrapolation in quark mass, finite volume…

High Energy Physics - Lattice · Physics 2008-11-26 C. Bernard T. Blum , C. DeTar , Steven Gottlieb , Urs M. Heller , J. Hetrick , K. Rummukainen , R. Sugar , D. Toussaint , M. Wingate

To reduce errors in light-quark mass determinations, it is now necessary to consider electromagnetic contributions to light-meson masses. Calculations using staggered quarks and quenched photons are currently underway. Suitably-extended…

High Energy Physics - Lattice · Physics 2010-11-18 C. Bernard , E. D. Freeland

The electromagnetic properties of the baryon octet are calculated in quenched QCD on a 20^3 x 40 lattice with a lattice spacing of 0.128 fm using the fat-link irrelevant clover (FLIC) fermion action. FLIC fermions enable simulations to be…

High Energy Physics - Lattice · Physics 2010-03-04 S. Boinepalli , D. B. Leinweber , A. G. Williams , J. M. Zanotti , J. B. Zhang

A large-N_f expansion is used to compute the partially quenched chiral condensate of QCD in the microscopic finite-volume scaling region.

High Energy Physics - Lattice · Physics 2009-10-31 Poul H. Damgaard

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

Bound states of heavy $\bar{q}q$ quarks are reviewed within the context of QCD. First of all, we consider the calculations which can be performed {\sl ab initio}, which includes $\bar{t}t$ with principal quantum number $n$ up to four,…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. J. Yndurain

Algorithmic progress in recent years made it possible to simulate QCD with Nf=2 flavours of O(a)-improved Wilson fermions at very light quark masses. We present the current results for baryon spectrum states, the nucleon axial coupling and…

We extend to quenched QCD an earlier investigation of the chiral structure of the masses of the nucleon and the delta in lattice simulations of full QCD. Even after including the meson-loop self-energies which give rise to the leading and…

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

The behavior of quenched QCD at nonzero chemical potential $\mu$ has been a long-standing puzzle. An explicit solution is found using the random matrix approach to chiral symmetry breaking. At nonzero $\mu$ the quenched QCD is not a simple…

High Energy Physics - Lattice · Physics 2009-10-28 M. A. Stephanov

We improve a previous quenched result for heavy-light pseudoscalar meson decay constants with the light quark taken to be the strange quark. A finer lattice resolution (a ~ 0.05 fm) in the continuum limit extrapolation of the data computed…

High Energy Physics - Lattice · Physics 2008-11-26 Michele Della Morte , Stephan Durr , Damiano Guazzini , Jochen Heitger , Andreas Juttner , Rainer Sommer

We present new results for light quark masses. The calculations are performed using two flavours of $O(a)$ improved Wilson fermions. We have reached lattice spacings as small as $a \sim 0.07$fm and pion masses down to $m_{\pi} \sim 340$MeV…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , G. Schierholz , T. Streuer , H. Stüben , J. M. Zanotti

I present preliminary results on the light quark masses from a partially quenched analysis of UKQCD's dynamical datasets.

High Energy Physics - Lattice · Physics 2015-06-25 D. J. Hepburn , UKQCD Collaboration

We study the signs of criticality in conserved charge fluctuations and related observables of finite temperature QCD at vanishing chemical potential, as we approach the chiral limit of two light quarks. Our calculations have been performed…

High Energy Physics - Lattice · Physics 2021-10-28 Mugdha Sarkar , Olaf Kaczmarek , Frithjof Karsch , Anirban Lahiri , Christian Schmidt

We compute fermionic observables relevant to the study of chiral symmetry in quenched QCD using the Overlap-Dirac operator for a wide range of the fermion mass. We use analytical results to disentangle the contribution from exact zero modes…

High Energy Physics - Lattice · Physics 2009-10-31 Robert G. Edwards , Urs M. Heller , Rajamani Narayanan

Using the finite-range regularisation (FRR) of chiral effective field theory, the chiral extrapolation formula for the vector meson mass is derived for the case of partially-quenched QCD. We re-analyse the dynamical fermion QCD data for the…

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

We examine quenched chiral logarithms in lattice QCD with overlap Dirac quarks. From our data of m_pi^2, we determine the coefficient of quenched chiral logarithm delta = 0.203(14), 0.176(17), 0.193(17) and 0.200(13) for lattices of sizes…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu , Tung-Han Hsieh