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arXiv · hep-ph/9902393

Simplification of Higher-Twist Evolution in the Large N_c Limit: Why and Why Not

Xiangdong Ji·Jonathan Osborne
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Abstract

Working in the light-cone gauge, we find a simple procedure to calculate the autonomous one-loop Q^2 evolution of the twist-three part of the nucleon g_T(x, Q^2) structure function in the large-N_c limit. Our approach allows us to investigate the possibility of a similar large-N_c simplification for other higher-twist evolutions. In particular, we show that it does not occur for the twist-four part of the f_4(x, Q^2), g_3(x, Q^2) and h_3(x, Q^2) distributions. We also argue that the simplification of the twist-three evolution does not persist beyond one loop.

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Xiangdong Ji, Jonathan Osborne. 1999-02-18. Simplification of Higher-Twist Evolution in the Large N_c Limit: Why and Why Not. https://doi.org/10.1007/s100529900095

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