Speaker
Dr
Jongkuk Kim
(Chung-Ang University)
Description
The Belle II Collaboration recently announced the first observation of the 𝐵 → 𝐾 + 𝜈 𝜈 decay process. This decay channel provides a particularly clean signal and allows for high theoretical precision. However, their measurement shows a 2.7𝜎 deviation from the Standard Model prediction. To address this excess, we study a scalar dark matter model. Assuming a dark 𝑈 (1)𝑋≡𝑈(1)𝐿𝜇−𝐿𝜏 symmetry, this symmetry is spontaneously broken to a local discrete symmetry, which guarantees the stability of dark matter. Within this framework, we can simultaneously explain the recent excess in B r (𝐵→𝐾+ 𝜈𝜈) reported by the Belle II Collaboration and the observed relic abundance of dark matter.