A new study has calculated the radiative and Dalitz decay rates of the upsilon Y(1S) meson into an eta_b (η_b) meson. Researchers used the Covariant Confined Quark Model to predict the hadronic form factor, the radiative decay constant, and the branching fractions of these decays. These calculations are crucial for understanding heavy meson interactions and for future searches for new physics beyond the Standard Model.

Within the framework of the Standard Model, the study predicts a radiative decay width Γ(Y(1S)→η_b γ) = 9.3(9) eV and a Dalitz decay width Γ(Y(1S)→η_b e⁺e⁻) = 4.8(5)×10⁻² eV. These theoretical predictions provide precise benchmark values that can be compared with future experimental data. The accuracy of these calculations is fundamental for identifying any deviations that could indicate the presence of phenomena not explained by the Standard Model.

The work also investigates the possible contribution of the hypothetical X17 vector boson, proposed by the ATOMKI experiment to explain an anomaly in the decays of beryllium-8 nuclei, to the Dalitz decay channel Y(1S)→η_b e⁺e⁻. Although the Standard Model does not predict the existence of the X17, its potential influence on Dalitz decays of heavy mesons like the Y(1S) is an active area of research. Searching for such anomalies in different physical systems is key to validating or refuting the existence of exotic particles.