QCD Hidden-Color Hexa-diquark in the Central Core of Nuclei

Abstract

Hidden-color configurations are a key prediction of QCD with important physical consequences. In this work we examine a QCD color-singlet configuration in nuclei formed by combining six scalar $[ud]$ diquarks in a strongly bound $\mathrm{SU}(3{)}_{\mathrm{C}}$ channel. The resulting hexadiquark state is a charge-2, spin-0, baryon number-4, isospin-0, color-singlet state. It contributes to alpha clustering in light nuclei and to the additional binding energy not saturated by ordinary nuclear forces in \he as well as the alpha-nuclei sequence of interest for nuclear astrophysics. We show that the strongly bound combination of six scalar isospin-0 $[ud]$ diquarks within the nuclear wave function - relative to free nucleons - provides a natural explanation of the EMC effect measured by the CLAS collaboration's comparison of nuclear parton distribution function ratios for a large range of nuclei. These experiments confirmed that the EMC effect; i.e., the distortion of quark distributions within nuclei, is dominantly identified with the dynamics of neutron-proton (``isophobic'') short-range correlations within the nuclear wave function rather than proton-proton or neutron-neutron correlations.

arXiv comment9 pages. References with positive preliminary results from the MARATHON experiment added, clarifications and minor edits. Version accepted for publication

References in corpus (4)

• Quantum Chromodynamics and Other Field Theories on the Light Cone
• Evidence for the Strong Dominance of Proton-Neutron Correlations in Nuclei
• Short Range Correlations and the EMC Effect
• Essential elements for nuclear binding

Cited by in corpus (4)

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• Conceptual design of the Spin Physics Detector
• Charm jets as a probe for strangeness at the future Electron-Ion Collider
• Diffractive Dissociation of Alpha Particles as a Test of Isophobic Short-Range Correlations inside Nuclei