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arXiv · hep-ph/9703363

Spin-Dependent Twist-Four Matrix Elements from g_1 Data in the Resonance Region

Xiangdong Ji·W. Melnitchouk
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Abstract

Matrix elements of spin-dependent twist-four operators are extracted from recent data on the spin-dependent g_1 structure function of the proton and deuteron in the resonance region. We emphasize the need to include the elastic contributions to the first moments of the structure functions at Q^2 < 2 GeV^2. The coefficients of the 1/Q^2 corrections to the Ellis-Jaffe sum rules are found to be 0.04 \pm 0.02 and 0.03 \pm 0.04 GeV^2 for the proton and neutron, respectively.

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Xiangdong Ji, W. Melnitchouk. 1997-03-19. Spin-Dependent Twist-Four Matrix Elements from g_1 Data in the Resonance Region. https://doi.org/10.1103/physrevd.56.r1

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