Author/Authors :
M. G?ckeler، نويسنده , , R. R. Horsley، نويسنده , , D. Pleiter، نويسنده , , P.E.L. Rakow، نويسنده , , G. Schierholz، نويسنده , , C.M. Maynard، نويسنده , , D.G. Richards، نويسنده ,
Abstract :
We present a calculation of the mass of the lowest-lying negative-parity J=1/2− state in quenched QCD. Results are obtained using a non-perturbatively O(a)-improved clover fermion action, and a splitting is found between the mass of the nucleon, and its parity partner. The calculation is performed on two lattice volumes and at three lattice spacings, enabling a study of both finite-volume and finite lattice-spacing uncertainties. A comparison is made with results obtained using the unimproved Wilson fermion action.
