Search for a muonphilic scalar $X_0$ or vector $X_1$ via $J/\psi \to {\mu }^{+}{\mu }^{-}+\mathrm{invisible}$ decays at BESII

BESIII Collaboration, M. Ablikim, M. N. Achasov +619

A light scalar $X_0$ or vector $X_1$ particles have been introduced as a possible explanation for the $(g-2{)}_{\mu }$ anomaly and dark matter phenomena. Using $(8.998\pm 0.039)\times…