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Kwiecinski evolution of unintegrated parton distributions

Wojciech Broniowski·Enrique Ruiz Arriola
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Abstract

The Kwiecinski evolution of unintegrated parton distributions (UPDs) in the transverse-coordinate space is analyzed with the help of the Mellin transform. Numerical results are presented for the unintegrated pion distributions with a simple valence-like initial condition at the low scale, which follows from chiral large-Nc quark models. The effect of spreading of UPDs in the transverse momentum with the increasing scale is confirmed, with growing asymptotically as Q^2 alpha(Q^2). Formal aspects of the equations, such as the limits of UPDs at x -> 0, x -> 1, and at low and large b, are straightforward to obtain with our method.

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Wojciech Broniowski, Enrique Ruiz Arriola. 2004-07-26. Kwiecinski evolution of unintegrated parton distributions. https://arxiv.org/abs/hep-ph/0407295

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