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Spin-3/2 Nucleon and Delta Baryons in Lattice QCD

J. M. Zanotti·D. B. Leinweber·A. G. Williams·J. B. Zhang·W. Melnitchouk·S. Choe
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Abstract

We present first results for masses of spin-3/2 N and Delta baryons in lattice QCD using Fat-Link Irrelevant Clover (FLIC) fermions. Spin-3/2 interpolating fields providing overlap with both spin-3/2 and spin-1/2 states are considered. In the isospin-1/2 sector, we observe, after appropriate spin and parity projection, a strong signal for the J^P=3/2^- state together with a weak but discernible signal for the 3/2^+ state with a mass splitting near that observed experimentally. We also find good agreement between the 1/2^+/- masses and earlier nucleon mass simulations with the standard spin-1/2 interpolating field. For the isospin-3/2 Delta states, clear mass splittings are observed between the various 1/2^+/- and 3/2^+/- channels, with the calculated level orderings in good agreement with those observed empirically.

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J. M. Zanotti, D. B. Leinweber, A. G. Williams, J. B. Zhang, W. Melnitchouk, S. Choe. 2003-04-01. Spin-3/2 Nucleon and Delta Baryons in Lattice QCD. https://doi.org/10.1103/physrevd.68.054506

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