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Related papers: Pion Form Factor with Overlap Fermion

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We present results towards the calculation of the pion electric form factor and structure function on a $16^3\times 24$ lattice using charge overlap. By sacrificing Fourier transform information in two directions, it is seen that the…

High Energy Physics - Lattice · Physics 2009-10-22 Walter Wilcox , B. Andersen-Pugh

Moments of generalised parton distributions can be related to off-forward matrix elements of local operators. We calculate a few of the leading twist matrix elements for the pion on the lattice. The simulations are performed using two…

High Energy Physics - Lattice · Physics 2008-11-26 D. Brömmel , M. Diehl , M. Göckeler , Ph. Hägler , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , J. M. Zanotti

We calculate the electromagnetic pion form factor in lattice QCD with 2+1 flavors of the dynamical overlap quarks. Up and down quark masses are set below their physical values so that the system is in the so-called epsilon regime with the…

High Energy Physics - Lattice · Physics 2014-09-02 H. Fukaya , S. Aoki , S. Hashimoto , T. Kaneko , H. Matsufuru , J. Noaki

We present an update on our on-going project to compute hadronic observables for Nf=2 flavours of O(a) improved Wilson fermions at small lattice spacings. The procedure to determine the lattice scale via the mass of the Omega baryon is…

High Energy Physics - Lattice · Physics 2011-01-27 B. B. Brandt , S. Capitani , M. Della Morte , D. Djukanovic , G. von Hippel , B. Jäger , A. Jüttner , B. Knippschild , H. Wittig

Results for Monte Carlo calculations of the electromagnetic vector and scalar form factors of the pion in a quenched simulation are presented. We work with two different lattice volumes up to a spatial size of 2.4 fm at a lattice spacing of…

High Energy Physics - Lattice · Physics 2008-11-26 Stefano Capitani , Christof Gattringer , C. B. Lang

A numerical investigation of time-separated charge overlap measurements is carried out for the pion in the context of lattice QCD using smeared Wilson fermions. The evolution of the charge distribution function is examined and the expected…

High Energy Physics - Lattice · Physics 2009-10-22 Walter Wilcox

We present results from the QCDSF/UKQCD collaboration for the electromagnetic and semi-leptonic form factors for the hyperons. The simulations are performed on our new ensembles generated with 2+1 flavours of dynamical O(a)-improved Wilson…

High Energy Physics - Lattice · Physics 2011-02-18 M. Göckeler , Ph. Hägler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , H. Stüben , F. Winter , J. M. Zanotti

In this work, we investigate the time-like pion form factor from lattice QCD in the isosymmetric limit, a quantity that plays an important role in understanding hadron physics with substantial phenomenological applications. This observable…

High Energy Physics - Lattice · Physics 2026-03-05 Gabriele Morandi , Mattia Bruno , Francesca Argia Bresciani , Christoph Lehner , Julian Parrino

We present results for Monte Carlo calculations of the electromagnetic vector and scalar form factors of the pion in a quenched simulation. We work at a lattice spacing of 0.15 fm and use two lattice volumes up to a spatial size of 2.4 fm.…

High Energy Physics - Lattice · Physics 2007-05-23 Stefano Capitani , Christof Gattringer , C. B. Lang

We report on the lowest moment of parton distribution functions and generalized form factors for the pion at several values of the momentum transfer. Calculations are performed for N_f=2 flavors of O(a) improved Wilson fermions with pion…

High Energy Physics - Lattice · Physics 2013-12-02 G. Bali , S. Collins , B. Glässle , M. Göckeler , N. Javadi-Motaghi , J. Najjar , W. Söldner , A. Sternbeck

We report on a calculation of $B_K$ with two-flavor dynamical overlap fermions on a $16^3 \times 32$ lattice at $a\sim 0.12$ fm. The results are compared with the PQChPT prediction of quark mass dependence. The systematic errors due to…

High Energy Physics - Lattice · Physics 2008-11-26 JLQCD Collaboration , N. Yamada , S. Aoki , H. Fukaya , S. Hashimoto , J. Noaki , T. Kaneko , H. Matsufuru , T. Onogi

We present a comparison of a number of iterative solvers of linear systems of equations for obtaining the fermion propagator in lattice QCD. In particular, we consider chirally invariant overlap and chirally improved Wilson (maximally)…

High Energy Physics - Lattice · Physics 2015-10-27 T. Chiarappa , K. Jansen , K. -I. Nagai , M. Papinutto , L. Scorzato , A. Shindler , C. Urbach , U. Wenger , I. Wetzorke

We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…

We report on the progress of our calculation of form factors for the exclusive semileptonic decay of $B$ mesons to pions on $2+1$ flavour lattices with spacings from $0.080~\mathrm{fm}$ down to $0.044~\mathrm{fm}$. Using the M\"{o}bius…

High Energy Physics - Lattice · Physics 2018-11-02 Brian Colquhoun , Shoji Hashimoto , Takashi Kaneko

We present preliminary results for the D_s meson spectroscopy study on the 2+1 flavour domain wall fermion lattice configurations, generated with the Iwasaki gauge action at beta=2.13 by the RBC-UKQCD collaboration. The simulations are on…

High Energy Physics - Lattice · Physics 2008-11-26 Chris Allton , Chris Maynard , Aurora Trivini , Robert Tweedie

We perform a lattice QCD calculation of the \pi^0\to\gamma\gamma transition form factor and the associated decay width. We use a Euclidean time integral of the relevant three-point function to compute the decay amplitude for two-photon…

High Energy Physics - Lattice · Physics 2012-11-13 Xu Feng , Sinya Aoki , Hidenori Fukaya , Shoji Hashimoto , Takashi Kaneko , Jun-ichi Noaki , Eigo Shintani

We compare overlap fermions, which are chirally invariant, and Wilson twisted mass fermions in the approach to the chiral limit. Our quenched simulations reveal that with both formulations of lattice fermions pion masses of O(250 MeV) can…

We present a status report of our calculation of the electromagnetic form factor of the pion on the PACS-CS gauge field configurations generated using Iwasaki gauge action and Wilson-clover quark action for 2 + 1 flavors of light dynamical…

High Energy Physics - Lattice · Physics 2011-02-01 CS Collaboration

We present a formula that allows one to calculate the pion form factor in the timelike region 2mpi <= sqrt{s} <= 4mpi in lattice QCD. The form factor quantifies the contribution of two-pion states to the vacuum polarization. It must be…

High Energy Physics - Lattice · Physics 2012-04-04 Harvey B. Meyer

We perform hybrid Monte Carlo simulation of (2+1+1)-flavors lattice QCD with the optimal domain-wall fermion (which has the effective 4D Dirac operator exactly equal to the Zolotarev optimal rational approximation of the overlap Dirac…

High Energy Physics - Lattice · Physics 2017-02-09 Yu-Chih Chen , Ting-Wai Chiu