Document Type


Publication Date




Publication Title

Physical Review Letters






092002 (6 pp.)


Mechanisms of spin-flavor SU(6) symmetry breaking in quantum chromodynamics (QCD) are studied via an extraction of the free neutron structure function from a global analysis of deep inelastic scattering (DIS) data on the proton and on nuclei from A = 2 (deuterium) to 208 (lead). Modification of the structure function of nucleons bound in atomic nuclei (known as the EMC effect) are consistently accounted for within the framework of a universal modification of nucleons in short-range correlated (SRC) pairs. Our extracted neutron-to-proton structure function ratio Fn2/Fp2 becomes constant for xB ≥ 0.6, equaling 0.47 ± 0.04 as xB → 1, in agreement with theoretical predictions of perturbative QCD and the Dyson-Schwinger equation, and in disagreement with predictions of the scalar diquark dominance model. We also predict F32He/F32H, recently measured, as yet unpublished, by the MARATHON Collaboration, the nuclear correction function that is needed to extract Fn2/Fp2 from F32He/F32H, and the theoretical uncertainty associated with this extraction.


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Original Publication Citation

Segarra, E. P., Schmidt, A., Kutz, T., Higinbotham, D. W., Piasetzky, E., Strikman, M., . . . Hen, O. (2020). Neutron valence structure from nuclear deep inelastic scattering. Physical Review Letters, 124(9), 6 pp. doi:10.1103/PhysRevLett.124.092002


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