Helicity Dependent Distribution Functions of the Proton and $\Lambda$ and $\Sigma^0$ Baryons
Abstract
Using continuum Schwinger function methods, a coherent set of predictions for proton, and distribution functions (DFs) has been made available -- both helicity dependent and unpolarised. The results and comparisons between them reveal impacts of diquark correlations and SU-flavour symmetry breaking, some of which are highlighted in this contribution. For instance: in-proton ratios of helicity-dependent/unpolarised valence-quark DFs are presented; it is highlighted that, were it not for the presence of axialvector diquarks in the , the valence strange quark would carry none of the spin; and the sign and size of polarised gluon DFs is discussed -- at a scale typical of modern measurements, gluon partons carry roughly 40% of each octet baryon's spin.
Keywords
Cite
@article{arxiv.2601.02587,
title = {Helicity Dependent Distribution Functions of the Proton and $\Lambda$ and $\Sigma^0$ Baryons},
author = {Yang Yu and Peng Cheng and Hui-Yu Xing and Daniele Binosi and Craig D. Roberts},
journal= {arXiv preprint arXiv:2601.02587},
year = {2026}
}
Comments
9 pages, 1 figure. Contribution to the proceedings of the 26th International Symposium on Spin Physics (SPIN25) -- A Century of Spin, 2025 September 22-26, Qingdao Haitian Hotel, Qingdao, Shandong Province, China