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New QCD Sum Rules for Nucleon Axial Vector Coupling Constants

Frank X. Lee·Derek B. Leinweber·Xuemin Jin
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Abstract

New QCD sum rules for the nucleon axial-vector current coupling constants are derived. One set is derived from a generalized correlator of spin-1/2 interpolating fields, and the other with a mixed correlator of spin-1/2 and spin-3/2 fields. Using a recently-developed Monte-Carlo based uncertainty analysis and techniques for determining the optimal interpolating fields, the predicative ability of QCD sum rules for axial-vector current coupling constants are determined. We find the previous studies of this matrix element are based on an invalid sum rule. A combined analysis of this sum rule together with the nucleon mass sum rules yields $g_A=1.48\pm^{1.06}_{0.65}$. The relative error of approximately 60% is large compared to a 10% error for the nucleon mass obtained from the same input parameters.

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Frank X. Lee, Derek B. Leinweber, Xuemin Jin. 1996-06-13. New QCD Sum Rules for Nucleon Axial Vector Coupling Constants. https://arxiv.org/abs/nucl-th/9606026

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