Studies of Hadron Spectroscopy at Belle and Belle II

Abstract

The Belle and Belle II experiments have collected an 1.6 ab${}^{-1}$ sample of $e^{+}{e}^{-}$ collision data at center-of-mass energies near the ${\rm Y}(nS)$ resonances. In particular, the Belle II experiment collected a 19.2 fb${}^{-1}$ sample of data at center-of-mass energies near the ${\rm Y}(10753)$ resonance. We study the following processes: $e^{+}{e}^{-}\to {\rm Y}(nS)\eta$, $e^{+}{e}^{-}\to \gamma X_b({\chi }_{bJ}{\pi }^{+}{\pi }^{-})$, and $e^{+}{e}^{-}\to {\chi }_{bJ}(1P)\gamma$. These results provide additional information about the nature of the ${\rm Y}(10753)$ resonance and nearby structures. In addition, we measure the $B^0$ and $B^{+}$ meson mass difference, and $\sigma \left(e^{+}{e}^{-}\to J/\psi p\bar{p}\right)$ over a range of center-of-mass energies accessed via initial-state radiation.

Proceedings for 32nd International Symposium on Lepton Photon Interactions at High Energies