English
Related papers

Related papers: Approximate actions for dynamical fermions

200 papers

I review recent developments in lattice QCD. I first give an overview of its formalism, and then discuss lattice discretizations of fermions. We then turn to a description of the quenched approximation and why it is disappearing as a…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thomas DeGrand

We present results for the b \bar b spectrum obtained using an O(M_bv^6)-correct non-relativistic lattice QCD action. Propagators are evaluated on SESAM's three sets of dynamical gauge configurations generated with two flavours of Wilson…

High Energy Physics - Lattice · Physics 2009-10-30 A. Spitz , N. Eicker , J. Fingberg , S. Güsken , H. Hoeber , Th. Lippert , K. Schilling , J. Viehoff

We discuss a proposal for the construction of lattice QCD with gauge action, fermionic action, theta-term, and the operators all based on the lattice Dirac operator D with exact chiral symmetry. The simplest regularization of this type uses…

High Energy Physics - Lattice · Physics 2008-11-26 Ivan Horvath

As a direct source of information on chiral symmetry breaking within QCD, the sigma commutator is of considerable importance. With recent advances in the calculation of hadron masses within full QCD it is of interest to see whether the…

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

We present numerical simulation of QCD with two dynamical quark flavors described by the overlap fermion action on a $16^3\times 32\times (0.12 {\rm fm})^4$ lattice. We calculate pseudo-scalar masses and decay constants and investigate…

High Energy Physics - Lattice · Physics 2009-04-14 J. Noaki , S. Aoki , H. Fukaya , S. Hashimoto , T. Kaneko , H. Matsufuru , T. Onogi , E. Shintani , N. Yamada

We present results on the QCD equation of state, obtained with two different improved dynamical staggered fermion actions and almost physical quark masses. Lattice cut-off effect are discussed in detail as results for three different…

High Energy Physics - Lattice · Physics 2008-10-06 Christian Schmid , for RBC-Bielefeld , HotQCD Collaborations

This review article summarizes recent lattice QCD results for $D$ and $D_s$ meson leptonic and semileptonic decays. Knowing the meson decay constants and semileptonic form factors from theory, one can extract CKM elements $V_{cd}$ and…

High Energy Physics - Lattice · Physics 2013-11-28 Jonna Koponen

In our earlier work, the charge and matter radial distributions of heavy-light mesons were measured on a 16^3 times 24 lattice with a lattice spacing of a = 0.17 fm and a light quark mass about that of the strange quark. Several major…

High Energy Physics - Lattice · Physics 2017-08-23 A. M. Green , J. Koponen , P. Pennanen , C. Michael

We present an overview of our project of large-scale simulations with dynamical overlap fermions. The first production run in two-flavor QCD is on-going using the Iwasaki gauge action on a 16^3 \times 32 lattice at the lattice spacing of…

We present technical details of an analysis of pseudo-scalar data from a QCD simulation with staggered fermions. The data were obtained close to the physical point with an inverse lattice spacing of about 3 GeV, and $N_f=2+1+1$. We compare…

High Energy Physics - Lattice · Physics 2019-10-25 Maximilian Ammer , Stephan Durr

I extend to QCD an efficient method for lattice gauge theory with dynamical fermions. Once the eigenvalues of the Dirac operator and the density of states of pure gluonic configurations at a set of plaquette energies (proportional to the…

High Energy Physics - Lattice · Physics 2009-11-07 Xiang-Qian Luo

We introduce the Pad\'e--Z$_2$ (PZ) stochastic estimator for calculating determinants and determinant ratios. The estimator is applied to the calculation of fermion determinants from the two ends of the Hybrid Monte Carlo trajectories with…

High Energy Physics - Lattice · Physics 2016-08-25 C. Thron , S. J. Dong , K. F. Liu , H. P. Ying

Moments of light cone quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD at $\beta = 5.5$ and $\beta = 5.3$ using Wilson fermions on $ 16^3 \times 32 $ lattices. These results are combined with…

We develop an implementation for a recently proposed Noisy Monte Carlo approach to the simulation of lattice QCD with dynamical fermions by incorporating the full fermion determinant directly. Our algorithm uses a quenched gauge field…

High Energy Physics - Lattice · Physics 2009-11-07 B. Joo , I. Horvath , K. F. Liu

Once the quark chemical potential $\mu$ is introduced in finite density QCD, the fermion determinant appeared in the path integral measure becomes complex. In order to investigate the phase effect of SU(3) lattice QCD (2-flavors), we…

High Energy Physics - Lattice · Physics 2009-11-10 Y. Sasai , A. Nakamura , T. Takaishi

We study QCD with two flavors of dynamical Wilson fermions at $\beta = 5.5$ and three values of $\kappa$. The corresponding pion masses are 0.375, 0.324 and 0.262 in lattice units, with pion to rho mass ratios of 0.76, 0.71 and 0.62,…

High Energy Physics - Lattice · Physics 2009-10-28 K. M. Bitar , R. G. Edwards , U. M. Heller , A. D. Kennedy

We investigate how the topological charge density in lattice QCD simulations is affected by violations of chiral symmetry caused by the fermion action. To this end we compare lattice configurations generated with a number of different…

High Energy Physics - Lattice · Physics 2012-01-10 Falk Bruckmann , Nigel Cundy , Florian Gruber , Thomas Lippert , Andreas Schäfer

For QCD with Wilson fermions at isospin chemical potential we study the finite phase transition on an $8^3\times4$ lattice at $\kappa=0.15$. We use two gauge actions: Wilson action and DBW2 action. Both actions give the same results. The…

High Energy Physics - Lattice · Physics 2009-11-10 A. Nakamura , T. Takaishi

We report on a direct lattice calculation of the neutron EDM(NEDM) using the external electric field method in both quenched and full QCD. In quenched QCD, we use a $24^3\times 32$ lattice at $\beta=2.6$ with the Iwasaki gauge action and…

High Energy Physics - Lattice · Physics 2008-11-26 E. Shintani , S. Aoki , N. Ishizuka , K. Kanaya , Y. Kuramashi , M. Okawa , A. Ukawa , T. Yoshié

We consider recent progress in algorithms for generating gauge field configurations that include the dynamical effects of light fermions. We survey what has been achieved in recent state-of-the-art computations, and examine the trade-offs…

High Energy Physics - Lattice · Physics 2009-11-10 A. D. Kennedy