Probing the ATOMKI X17 vector boson using Dalitz decays $V\to P{e}^{+}{e}^{-}$

Abstract

Recent anomalies observed in $e^{+}{e}^{-}$ nuclear transitions of ${}^8\text{Be}$, ${}^4\text{He}$, and ${}^{12}\text{C}$ by the ATOMKI collaboration may hint at the existence of a vector boson with a mass around 17 MeV, referred to as X17. If it exists, this boson would also affect similar processes in particle physics, including the Dalitz decays of vector mesons. Recently, the BESIII collaboration measured the Dalitz decay $D^{\ast 0}\to D^0{e}^{+}{e}^{-}$ for the first time and reported a $3.5\sigma$ excess over the theoretical prediction based on the vector meson dominance (VMD) model. This excess may be another signal of the X17. In this study, we investigate the possible effects of the X17 on the Dalitz decays $D_{(s)}^{\ast }\to D_{(s)}{e}^{+}{e}^{-}$, $B_{(s)}^{\ast }\to B_{(s)}{e}^{+}{e}^{-}$, and $J/\psi \to {\eta }_c{e}^{+}{e}^{-}$. The required hadronic form factors are calculated within the framework of our covariant confined quark model, without relying on heavy quark effective theory or the VMD model. We present predictions for the Dalitz decay widths and the ratios $R_{ee}(V)\equiv \Gamma (V\to P{e}^{+}{e}^{-})/\Gamma (V\to P\gamma )$ within the Standard Model and in several new physics scenarios involving modifications due to the X17. Our results are compared with other theoretical calculations.

21 pages, 6 figures, typos corrected, references added. To be published in Chinese Physics C

References in corpus (37)

• Exclusive semileptonic and nonleptonic decays of the Bc meson
• Protophobic Fifth Force Interpretation of the Observed Anomaly in ${}^8$Be Nuclear Transitions
• Particle Physics Models for the 17 MeV Anomaly in Beryllium Nuclear Decays
• Study of the electromagnetic transition form-factors in η-> μ^+μ^-γand ω-> μ^+μ^-π^0 decays with NA60
• Search for a Hypothetical 16.7 MeV Gauge Boson and Dark Photons in the NA64 Experiment at CERN
• Improved limits on a hypothetical X(16.7) boson and a dark photon decaying into $e^{+}{e}^{-}$ pairs
• Relativistic constituent quark model with infrared confinement
• Rare baryon decays Lambda_b -> Lambda l+ l- (l=e, mu, tau) and Lambda_b -> Lambda gamma : Differential and total rates, lepton- and hadron-side forward-backward asymmetries
• A new anomaly observed in ${}^4$He supports the existence of the hypothetical X17 particle
• The exclusive rare decays B -> K l(bar) l and B_c -> D(D*) l(bar) l in a relativistic quark model
• Light Axial Vectors, Nuclear Transitions, and the ${}^8$Be Anomaly
• New anomaly observed in ${}^{12}$C supports the existence and the vector character of the hypothetical X17 boson
• One-photon decay of the tetraquark state $X(3872)\to \gamma +J/\psi$ in a relativistic constituent quark model with infrared confinement
• Four-quark structure of Zc(3900), Z(4430) and Xb(5568) states
• Dynamical Evidence For a Fifth Force Explanation of the ATOMKI Nuclear Anomalies
• QED Meson Description of the X17 and Other Anomalous Particles
• Implication of the hidden sub-GeV bosons for the $(g-2{)}_{\mu }$, ${}^8$Be-${}^4$He anomaly, proton charge radius, EDM of fermions and dark axion portal
• Can a protophobic vector boson explain the ATOMKI anomaly?
• Semileptonic Decays of Charmed Mesons to Light Scalar Mesons
• Study of the electromagnetic transitions $J/\psi \to P{l}^{+}{l}^{-}$ and probe dark photon
• Is There a Sign of New Physics in Beryllium Transitions?
• Measurement of $\mathcal{B}(J/\psi \to {\eta }^{\prime }{e}^{+}{e}^{-}$) and search for a dark photon
• Neutrino Constraints and the ATOMKI X17 Anomaly
• Atomki anomaly in gauged $U(1{)}_R$ symmetric model
• Test of the multiquark structure of $a_1(1420)$ in strong two-body decays
• Study of the electromagnetic Dalitz decays $\psi ({\rm Y})\to {\eta }_c({\eta }_b)l^{+}{l}^{-}$
• Search for new light vector boson using $J/\Psi$ at BESIII and Belle II
• Checking the ${}^8$Be anomaly with a two-arm electron positron pair spectrometer
• Radiative decays $D^*_{(s)}\to D_{(s)}γ$ in covariant confined quark model
• $D^{\ast }$ Polarization as an Additional Constraint on New Physics in the $b\to c\tau {\bar{\nu }}_{\tau }$ Transition
• Form-factor-independent test of lepton universality in semileptonic heavy meson and baryon decays
• Observation of the Dalitz Decay $D_s^{\ast +}\to D_s^{+}{e}^{+}{e}^{-}$
• Tests of the Atomki anomaly in lepton pair decays of heavy mesons
• On the Atomki nuclear anomaly after the MEG-II result
• Polarization observables in semileptonic $V\to P$ decays of quarkonia
• Observation of the electromagnetic Dalitz decay $D^{\ast 0}\to D^0{e}^{+}{e}^{-}$
• Electromagnetic Dalitz Decays of $D_{(s)}^{\ast }$ Mesons

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