Strangeness and glue in the nucleon from lattice QCD

Abstract

We study the strangeness contribution to nucleon matrix elements using Nf=2+1 dynamical clover fermion configurations generated by the CP-PACS/JLQCD collaboration. In order to evaluate the disconnected insertion (DI), we use the Z(4) stochastic method, along with unbiased subtraction from the hopping parameter expansion which reduces the off-diagonal noises in the stochastic method. Furthermore, we find that using many nucleon sources for each configuration is effective in improving the signal. Our results for the quark contribution to the first moment <x>_q in the DI, and the strangeness magnetic moment show that the statistical errors are under control with these techniques. We also study the gluonic contribution to the nucleon using the overlap operator to construct the gauge field tensor, F_{mu,nu}. The application to the calculation of first moment, <x>_G, gives a good signal in quenched lattice QCD.

7 pages, 4 figures; Talk given at 26th International Symposium on Lattice Field Field: Lattice 2008, Williamsburg, Virginia, USA, 14-19 Jul 2008

References in corpus (3)

• Moments of Nucleon's Parton Distribution for the Sea and Valence Quarks from Lattice QCD
• Gauge Field Strength Tensor from the Overlap Dirac Operator
• 2+1 flavor light hadron spectrum and quark masses with the O(a) improved Wilson-clover quark formalism

Cited by in corpus (9)

• A Lattice Study of Quark and Glue Momenta and Angular Momenta in the Nucleon
• Parton Distribution Function from the Hadronic Tensor on the Lattice
• Ratio of strange to $u/d$ momentum fraction in disconnected insertions
• Lattice QCD for Precision Nucleon Matrix Elements
• Quark and Glue Momenta and Angular Momenta in the Proton --- a Lattice Calculation
• Strange quark content of the nucleon
• The Flavor Structure of the Nucleon Sea
• Investigations of hadron structure on the lattice
• Strange quark momentum fraction from overlap fermion