Abstract
Recently a 6.8σ anomaly has been reported in the opening angle and invariant mass distributions of e+e− pairs produced in 8Be nuclear transitions. The data are explained by a 17 MeV vector gauge boson X that is produced in the decay of an excited state to the ground state, 8Be∗ → 8Be X, and then decays through X → e+e−. The X boson mediates a fifth force with a characteristic range of 12 fm and has millicharged couplings to up and down quarks and electrons, and a proton coupling that is suppressed relative to neutrons. The protophobic X boson may also alleviate the current 3.6σ discrepancy between the predicted and measured values of the muon’s anomalous magnetic moment.
Document Type
Article
Publication Date
8-11-2016
Digital Object Identifier (DOI)
https://doi.org/10.1103/PhysRevLett.117.071803
Funding Information
The work of J. L. F., B. F., I. G., J. S., T. M. P. T., and P. T. is supported in part by NSF Grant No. PHY-1316792. The work of S. G. is supported in part by the DOE Office of Nuclear Physics under Contract No. DE-FG02-96ER40989. J. L. F. is supported in part by a Guggenheim Foundation Grant and in part by Simons Investigator Grant No. 376204.
Repository Citation
Feng, Jonathan L.; Fornal, Bartosz; Galon, Iftah; Gardner, Susan; Smolinsky, Jordan; Tait, Tim M. P.; and Tanedo, Philip, "Protophobic Fifth-Force Interpretation of the Observed Anomaly in 8Be Nuclear Transitions" (2016). Physics and Astronomy Faculty Publications. 432.
https://uknowledge.uky.edu/physastron_facpub/432
Notes/Citation Information
Published in Physical Review Letters, v. 117, issue 7, 071803, p. 1-6.
© 2016 American Physical Society
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