Search for double charmonium decays of theP-wave spin-triplet bottomonium states
Search for double charmonium decays of theP-wave spin-triplet bottomonium states
Using a sample of 158 million $\Upsilon(2S)$ events collected with the Belle detector, we search for the first time for double charmonium decays of the $P$-wave spin-triplet bottomonium states ($\Upsilon(2S) \to \gamma \chi_{bJ}$, $\chi_{bJ} \to \jpsi \jpsi$, $\jpsi \psp$, $\psp \psp$ for J=0, 1, and 2). No significant $\chi_{bJ}$ signal …