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QCD Sum Rule Calculation of Twist-4 Corrections to Bjorken and Ellis-Jaffe Sum Rules

E. Stein·P. Gornicki·L. Mankiewicz·A. Schaefer
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Abstract

We calculate the twist-4 corrections to the integral of $g_1(x,Q^2)$ in the framework of QCD sum rules using an interpolating nucleon field which contains explicitly a gluonic degree of freedom. This information can be used together with previous calculations of the twist-3 contribution to the second moment of $g_2(x)$ to estimate the higher-twist corrections to the Ellis-Jaffe and Bjorken sum rules. We get $f^{(2)}(proton) = -0.037 \pm 0.006$ and $f^{(2)}(neutron) = -0.013 \pm 0.006$. Numerically our results roughly agree with those obtained by Balitsky, Braun and Kolesnichenko based on a sum rule for a simpler current. Our calculations are far more stable as tested within the sum rule approach but are more sensitive to less well known condensates.

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E. Stein, P. Gornicki, L. Mankiewicz, A. Schaefer. 1995-02-16. QCD Sum Rule Calculation of Twist-4 Corrections to Bjorken and Ellis-Jaffe Sum Rules. https://doi.org/10.1016/0370-2693(95)00544-u

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