Lattice Calculation of Baryon Masses using the Clover Fermion Action

LHPC Collaboration; D. G. Richards; QCDSF Collaboration; :; M. Gockeler; R. Horsley; D. Pleiter; P. E. L. Rakow; G. Schierholz; UKQCD Collaboration; C. M. Maynard

arXiv · nucl-th/0206049

Lattice Calculation of Baryon Masses using the Clover Fermion Action

LHPC Collaboration·D. G. Richards·QCDSF Collaboration·:·M. Gockeler·R. Horsley·D. Pleiter·P. E. L. Rakow·G. Schierholz·UKQCD Collaboration·C. M. Maynard

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Abstract

We present a calculation of the lowest-lying baryon masses in the quenched approximation to QCD. The calculations are performed using a non-perturbatively improved clover fermion action, and a splitting is found between the masses of the nucleon and its parity partner. An analysis of the mass of the first radial excitation of the nucleon finds a value considerably larger than that of the parity partner of the nucleon, and thus little evidence for the Roper resonance as a simple three-quark state

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LHPC Collaboration, D. G. Richards, QCDSF Collaboration, :, M. Gockeler, R. Horsley, D. Pleiter, P. E. L. Rakow, G. Schierholz, UKQCD Collaboration, C. M. Maynard. 2002-06-19. Lattice Calculation of Baryon Masses using the Clover Fermion Action. https://arxiv.org/abs/nucl-th/0206049

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