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arXiv · 2108.11493

Valence quark ratio in the proton

Zhu-Fang Cui·Fei Gao·Daniele Binosi·Lei Chang·Craig D. Roberts·Sebastian M. Schmidt
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Abstract

Beginning with precise data on the ratio of structure functions in deep inelastic scattering (DIS) from $^3$He and $^3$H, collected on the domain $0.19 \leq x_B \leq 0.83$, where $x_B$ is the Bjorken scaling variable, we employ a robust method for extrapolating such data to arrive at a model-independent result for the $x_B=1$ value of the ratio of neutron and proton structure functions. Combining this with information obtained in analyses of DIS from nuclei, corrected for target-structure dependence, we arrive at a prediction for the proton's valence-quark ratio: $\left. d_v/u_v \right|_{x_B\to 1} = 0.230 (57)$. Requiring consistency with this result presents a challenge to many descriptions of proton structure.

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Zhu-Fang Cui, Fei Gao, Daniele Binosi, Lei Chang, Craig D. Roberts, Sebastian M. Schmidt. 2021-08-25. Valence quark ratio in the proton. https://doi.org/10.1088/0256-307x%2F39%2F4%2F041401

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