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The evolution of the nonsinglet twist-3 parton distribution function

B. Geyer·D. Müller·D. Robaschik
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Abstract

The twist three contributions to the $Q^2$-evolution of the spin-dependent structure function $g_2(x_{Bj},Q^2)$ are considered in the non-local operator product approach. Defining appropriate twist three distribution function we derive their evolution equation for the nonsinglet case in leading order approximation. In the limit $x_{Bj} \rightarrow 1$ as well as in the large $N_c$ limit we confirm the result that the evolution of the nonsinglet part of $g_2$ is governed by a Gribov-Lipatov-Altarelli-Parisi equation.

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B. Geyer, D. Müller, D. Robaschik. 1996-11-27. The evolution of the nonsinglet twist-3 parton distribution function. https://arxiv.org/abs/hep-ph/9611452

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