A gauged, flavor-specific U(1)_X two-Higgs-doublet model can realize the axial-vector Z' couplings needed to explain the ATOMKI 8Be and 4He anomalies while evading current bounds.
Limit on the production of a low-mass vector boson in e +e− → Uγ, U → e+e− with the KLOE experiment
2 Pith papers cite this work. Polarity classification is still indexing.
abstract
The existence of a new force beyond the Standard Model is compelling because it could explain several striking astrophysical observations which fail standard interpretations. We searched for the light vector mediator of this dark force, the $\mathrm{U}$ boson, with the KLOE detector at the DA$\Phi$NE $\mathrm{e}^{+}\mathrm{e}^{-}$ collider. Using an integrated luminosity of 1.54 fb$^{-1}$, we studied the process $\mathrm{e}^{+}\mathrm{e}^{-} \to \mathrm{U}\gamma$, with $\mathrm{U} \to \mathrm{e}^{+}\mathrm{e}^{-}$, using radiative-return to search for a resonant peak in the dielectron invariant-mass distribution. We did not find evidence for a signal, and set a 90\%~CL upper limit on the mixing strength between the Standard Model photon and the dark photon, $\varepsilon^2$, at $10^{-6}$--$10^{-4}$ in the 5--520~MeV/c$^2$ mass range.
citation-role summary
citation-polarity summary
fields
hep-ph 2years
2026 2roles
background 1polarities
background 1representative citing papers
Reactor neutrino data from CONUS+ and Dresden-II combined with COHERENT and IceCube data singles out a region of neutrino and nuclear couplings consistent with the X17 particle.
citing papers explorer
-
Flavor specific chiral $U(1)_X$ framework for explaining the ATOMKI anomaly
A gauged, flavor-specific U(1)_X two-Higgs-doublet model can realize the axial-vector Z' couplings needed to explain the ATOMKI 8Be and 4He anomalies while evading current bounds.
-
The X17 Existence Hinted at by Nuclear Reactor Neutrinos
Reactor neutrino data from CONUS+ and Dresden-II combined with COHERENT and IceCube data singles out a region of neutrino and nuclear couplings consistent with the X17 particle.