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arXiv · 2210.17396

Parametrizations of collinear and k_T-dependent parton densities in a proton

N. A. Abdulov·A. V. Kotikov·A. V. Lipatov
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Abstract

A new type of parametrization for parton distribution functions in a proton, based on their $Q^2$-evolution at large and small $x$ values, is constructed. In our analysis, the valence and nonsinglet parts obey the Gross-Llewellyn-Smith and Gottfried sum rules, respectively. For the singlet quark and gluon densities momentum conservation is taken into account. Then, using the Kimber-Martin-Ryskin prescription, we extend the consideration to Transverse Momentum Dependent (TMD, or unintegrated) gluon and quark distributions in a proton, which currently plays an important role in a number of phenomenological applications. The analytical expressions for the latter, valid for both low and large $x$, are derived for the first time.

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N. A. Abdulov, A. V. Kotikov, A. V. Lipatov. 2022-10-31. Parametrizations of collinear and k_T-dependent parton densities in a proton. https://arxiv.org/abs/2210.17396

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