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arXiv · hep-ph/9507332

Analytic Approaches to the Evolution of Polarised Parton Distributions at Small $x$

T. Gehrmann·W. J. Stirling
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Abstract

The $Q^2$ evolution of polarised parton distributions at small $x$ is studied. Various analytic approximations are critically discussed. We compare the full evolution with that obtained from the leading-pole approximation to the splitting functions, and show that the validity of this approximation depends critically on the $x \to 0$ behaviour of the starting distributions. A new analytic solution which is valid at small $x$ is obtained, and its domain of applicability is discussed.

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T. Gehrmann, W. J. Stirling. 1995-07-18. Analytic Approaches to the Evolution of Polarised Parton Distributions at Small $x$. https://doi.org/10.1016/0370-2693(95)01229-x

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