QCD Sum Rules Calculation of the Singlet Axial Constant

A. V. Belitsky; O. V. Teryaev

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arXiv · hep-ph/9512376

QCD Sum Rules Calculation of the Singlet Axial Constant

A. V. Belitsky·O. V. Teryaev

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Abstract

We analyze the singlet axial form factor of the proton for small momentum transferred in the framework of QCD sum rules using the interpolating nucleon current which explicitly accounts for the gluonic degrees of freedom. As a result we come to the quantitative description of the singlet axial constant: G_A(0)=0.2. The bilocal power corrections play the most important role in the analysis.

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A. V. Belitsky, O. V. Teryaev. 1996-04-10. QCD Sum Rules Calculation of the Singlet Axial Constant. https://arxiv.org/abs/hep-ph/9512376

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