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arXiv · 2605.19918

Redetermination of proton sea distributions

Alim Ruzi·Bo-Qiang Ma
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Abstract

The shapes of light flavor sea quark distributions of the proton are examined directly from two rounds of NNLO global analysis of HERA $e^{\pm}p$ deep inelastic scattering cross section measurements, termed as HERAshape and the ATLAS measurement of $W^{\pm}/Z$ production from $pp$ collision at $\sqrt{s}$ = 7 TeV, termed as ATLASshape. An asymmetric distribution between anti-up ($\ubar$) quark and anti-down ($\dbar$) quark is found in both analysis, showing that the anti-up quark distribution exceeds over anti-down quark distribution in the momentum fraction range $x\in(10^{-2}, 1)$ of these partons. The Gottfried Sum Rule is reevaluated from these extracted parton distribution functions and the obtained value differs surprisingly from that of the NMC and the NuSea Collaborations.

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Alim Ruzi, Bo-Qiang Ma. 2026-05-19. Redetermination of proton sea distributions. https://arxiv.org/abs/2605.19918

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