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Excited Baryons from the FLIC Fermion Action

W. Melnitchouk·J. N. Hedditch·D. B. Leinweber·A. G. Williams·J. M. Zanotti·J. B. Zhang
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Abstract

Masses of positive and negative parity excited nucleons and hyperons are calculated in quenched lattice QCD using an O(a^2) improved gluon action and a fat-link clover fermion action in which only the irrelevant operators are constructed with fat links. The results are in agreement with earlier N* simulations with improved actions, and exhibit a clear mass splitting between the nucleon and its parity partner, as well as a small mass splitting between the two low-lying J^P={1/2}^- N* states. Study of different Lambda interpolating fields suggests a similar splitting between the lowest two {1/2}^- Lambda* states, although the empirical mass suppression of the Lambda*(1405) is not seen.

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W. Melnitchouk, J. N. Hedditch, D. B. Leinweber, A. G. Williams, J. M. Zanotti, J. B. Zhang. 2002-10-24. Excited Baryons from the FLIC Fermion Action. https://doi.org/10.1016/s0920-5632(03)01542-1

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