2022/06/29 by Valery Kubarovsky, Kubarovsky, Valery, Jennifer Rittenhouse West +3 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2206.14441
openalex publication_date 2022/06/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Observations of anomalous angular correlations in electron-positron pairs produced from excited states of 4He, 8Be and 12C nuclei have been suggested as due to the creation and subsequent decay of a new light particle of mass ∼17 MeV. In this work, we investigate the possibility that the source of the observed signals is a set of new excitation channels created by the 12-quark hidden-color Fock state within the \rm 4He nuclear wavefunction dubbed the ``hexadiquark.'' We calculate the invariant e+e- mass spectrum for the electromagnetic transition from a new excitation of 4He, estimating its differential and total decay width. We find that we can fit the shape of the anomalous signal with the QCD Fock state at excitation energy \rm E* = 17.9 ± 1 MeV and a Gaussian form factor for the electromagnetic decay. We address the physical issues with the fit parameters using properties of the hexadiquark state, in particular the three weakly repulsive \rm 6C interactions of \rm SU(3)C between diquark pairs. Experimental tests of our model are described in detail. In light of this work, we emphasize the need for independent experimental confirmation or refutation of the ATOMKI results as well as dedicated experiments to search for the proposed new excitations of \rm 4He and other α-cluster nuclei.