Small $x$ behaviour of the chirally-odd parton distribution $h_1(x,Q^2)$

R. Kirschner; L. Mankiewicz; A. Schäfer; L. Szymanowski

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arXiv · hep-ph/9606267

Small $x$ behaviour of the chirally-odd parton distribution $h_1(x,Q^2)$

R. Kirschner·L. Mankiewicz·A. Schäfer·L. Szymanowski

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Abstract

The small $x$ behaviour of the structure function $h_1(x,Q^2)$ is studied within the leading logarithmic approximation of perturbative QCD. There are two contributions relevant at small $x$. The leading one behaves like $(\frac{1}{x})^0$ i.e. it is just a constant in this limit. The second contribution, suppressed by one power of $x$, includes the terms summed by the GLAP equation. Thus for $h_1(x,Q^2)$ the GLAP asymptotics and Regge asymptotics are completely different, making $h_1(x,Q^2)$ quite an interesting quantity for the study of small $x$ physics.

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R. Kirschner, L. Mankiewicz, A. Schäfer, L. Szymanowski. 1996-06-07. Small $x$ behaviour of the chirally-odd parton distribution $h_1(x,Q^2)$. https://arxiv.org/abs/hep-ph/9606267

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