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arXiv · hep-lat/0201005

Baryon resonances from a novel fat-link fermion action

W. Melnitchouk·S. Bilson-Thompson·F. D. R. Bonnet·P. D. Coddington·D. B. Leinweber·A. G. Williams·J. M. Zanotti·J. B. Zhang·F. X. Lee
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Abstract

We present first results for masses of positive and negative parity excited baryons in lattice QCD using an O(a^2) improved gluon action and a Fat Link Irrelevant Clover (FLIC) fermion action in which only the irrelevant operators are constructed with fat links. The results are in agreement with earlier calculations of N^* resonances using improved actions and exhibit a clear mass splitting between the nucleon and its chiral partner, even for the Wilson fermion action. The results also indicate a splitting between the lowest J^P = 1/2^- states for the two standard nucleon interpolating fields.

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W. Melnitchouk, S. Bilson-Thompson, F. D. R. Bonnet, P. D. Coddington, D. B. Leinweber, A. G. Williams, J. M. Zanotti, J. B. Zhang, F. X. Lee. 2002-01-04. Baryon resonances from a novel fat-link fermion action. https://doi.org/10.1016/s0920-5632(02)01396-8

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