Excited Nucleon Resonance Properties from Lattice QCD
Abstract
We review the progress of the Lattice Hadron Physics Collaboration's ongoing efforts to determine the tower of excited nucleon resonances as predicted by QCD. The most common approach to this problem is to consider twopoint correlations of interpolating operators calculated using lattice QCD. We show that realistic interpolating operators are essential for accessing the states of interest and describe how such operators can be designed. We outline how a variant of the variational method combined with a systematic fitting approach can be used to extract finitevolume spectra from the Green's functions, and illustrate the efficacy of the approach by showing preliminary results using twoflavors of dynamical fermions. We outline the connection between the finitevolume spectra obtained from the lattice and the continuum resonance states measured in experiment, and conclude with a discussion of current limitations and ongoing improvements.
 Publication:

APS Division of Nuclear Physics Meeting Abstracts
 Pub Date:
 October 2007
 Bibcode:
 2007APS..DNP.BA004L