Is There a Sign of New Physics in Beryllium Transitions?

Abstract

We discuss the current status of the anomaly in beryllium-8 nuclear transitions recently reported in the angular distribution of internal conversion electron-positron pairs. We present a phenomenological analysis of the signal and review the models proposed to explain it, focusing on those involving a new light protophobic vector gauge boson. We also elaborate on the prospects of verifying the anomaly in present and future experiments.

arXiv comment19 pages + references, 10 figures; Invited talk given at the American Physical Society April Meeting 2017, Washington, DC, January 28, 2017; based mainly on arXiv:1604.07411 [hep-ph] and arXiv:1608.03591 [hep-ph]

References in corpus (38)

• Final Report of the Muon E821 Anomalous Magnetic Moment Measurement at BNL
• New Fixed-Target Experiments to Search for Dark Gauge Forces
• Quantum Monte Carlo calculations of A=8 nuclei
• Observation of Anomalous Internal Pair Creation in ${}^8$Be: A Possible Signature of a Light, Neutral Boson
• Improved predictions for g-2 of the muon and α_{\rm QED}(M_Z^2)
• Quantum Monte Carlo calculations of excited states in A = 6--8 nuclei
• Protophobic Fifth Force Interpretation of the Observed Anomaly in ${}^8$Be Nuclear Transitions
• ALPtraum: ALP production in proton beam dump experiments
• Unbroken B-L Symmetry
• Particle Physics Models for the 17 MeV Anomaly in Beryllium Nuclear Decays
• Muon g-2, Rare Kaon Decays, and Parity Violation from Dark Bosons
• Gauge Theory for Baryon and Lepton Numbers with Leptoquarks
• Dark photons from charm mesons at LHCb
• Constraints on Dark Photon from Neutrino-Electron Scattering Experiments
• Limit on the production of a low-mass vector boson in ${\mathrm{e}}^{+}{\mathrm{e}}^{-}\to \mathrm{U}\gamma$, $\mathrm{U}\to {\mathrm{e}}^{+}{\mathrm{e}}^{-}$ with the KLOE experiment
• Muon Anomaly and Dark Parity Violation
• Proposal to search for a dark photon in $e^{+}$ on target collisions at DA$\Phi$NE linac
• Light Weakly Coupled Axial Forces: Models, Constraints, and Projections
• Minimal Theory for Lepto-Baryons
• Theory for Baryon Number and Dark Matter at the LHC
• The light U boson as the mediator of a new force, coupled to a combination of Q, B, L and dark matter
• Light Axial Vectors, Nuclear Transitions, and the ${}^8$Be Anomaly
• Projections for Dark Photon Searches at Mu3e
• Theoretical framework to analyze searches for hidden light gauge bosons in electron scattering fixed target experiments
• Realistic model for a fifth force explaining anomaly in ${}^{8}B{e}^{\ast }\to {}^{8}Be{e}^{+}{e}^{-}$ Decay
• Quantum Monte Carlo calculations of electromagnetic transitions in 8Be with meson-exchange currents derived from chiral effective field theory
• A pair spectrometer for measuring multipolarities of energetic nuclear transitions
• Charge-symmetry breaking forces and isospin mixing in 8Be
• Protophobic Light Vector Boson as a Mediator to the Dark Sector
• Atomki anomaly and dark matter in a radiative seesaw model with gauged $B-L$ symmetry
• Probing a dark photon using rare leptonic kaon and pion decays
• The new interaction suggested by the anomalous ${}^8$Be transition sets a rigorous constraint on the mass range of dark matter
• Global Analysis of the Source and Detector Nonstandard Interactions Using the Short Baseline Neutrino- and Antineutrino-Electron Scattering Data
• Further search for a neutral boson with a mass around 9 MeV/c2
• Baryon Number as the Fourth Color
• B and L at the SUSY Scale, Dark Matter and R-parity Violation
• A Re-evaluation of Evidence for Light Neutral Bosons in Nuclear Emulsions
• Light gauge boson in rare $K$ decay

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• Tests of the Atomki anomaly in lepton pair decays of heavy mesons
• Could the 21-cm absorption be explained by the dark matter suggested by ${}^8$Be transitions?
• Dark Matter Raining on DUNE and Other Large Volume Detectors
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• On the question of quark confinement in the Abelian U(1) QED gauge interaction
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• Probing the ATOMKI X17 vector boson using Dalitz decays $V\to P{e}^{+}{e}^{-}$
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• Interpretation of the Galactic gamma-ray excess with the dark matter indicated by ${}^8$Be and ${}^4$He anomalous transitions