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arXiv · 2312.00809

Off-shell modifications of bound nucleons and parton distributions

S. I. Alekhin·S. A. Kulagin·R. Petti
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Abstract

We discuss results from our global QCD analyses including nuclear data off deuterium from various measurements, as well as off $^3$H and $^3$He targets from the MARATHON experiment. We simultaneously determine the parton distribution functions of the proton, the higher-twist terms, and the nucleon off-shell correction functions responsible for the modifications of the partonic structure in bound protons and neutrons. In particular, we study the neutron-proton asymmetry of the off-shell correction and its interplay with the treatment of the higher-twist terms. We observe that the data on the $^3$He/$^3$H cross section ratio are consistent with a single isoscalar off-shell function. We also provide our predictions on the ratio $F_2^n/F_2^p$ and on the $d$ and $u$ quark distributions in the proton and in the $^3$H and $^3$He nuclei.

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S. I. Alekhin, S. A. Kulagin, R. Petti. 2023-11-27. Off-shell modifications of bound nucleons and parton distributions. https://arxiv.org/abs/2312.00809

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