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arXiv · 2304.06998

Evolution of structure functions in momentum space

Tuomas Lappi·Heikki Mäntysaari·Hannu Paukkunen·Mirja Tevio
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Abstract

We formulate the momentum-space Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations for structure functions measurable in deeply inelastic scattering. We construct a six-dimensional basis of structure functions that allows for a full three flavor structure and thereby provides a way to calculate perturbative predictions for physical cross sections directly without unobservable parton distribution functions (PDFs) and without the associated scheme dependence. We derive the DGLAP equations to first non-zero order in strong coupling $\alpha_s$, but the approach can be pursued to arbitrary order in perturbation theory. We also numerically check our equations against the conventional PDF formulation.

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Tuomas Lappi, Heikki Mäntysaari, Hannu Paukkunen, Mirja Tevio. 2023-04-14. Evolution of structure functions in momentum space. https://doi.org/10.1140/epjc%2Fs10052-023-12365-2

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