000003909 001__ 3909 000003909 005__ 20231014190225.0 000003909 037__ $$aBELLE2-TALK-CONF-2023-154 000003909 041__ $$aeng 000003909 100__ $$aSeongbae Yang 000003909 245__ $$aHadron Spectroscopy at Belle and Belle II 000003909 260__ $$aMENU2023$$c2023-10-10 000003909 300__ $$amult. p 000003909 520__ $$aBelle II, which commenced data acquisition in 2019, has already yielded research results in hadron spectroscopy. The $e^{+}e^{-}$ collision data, taken at or near the $\Upsilon(4S)$ resonance, are well-suited for studying hadrons with a high-performance detector system. In this presentation, we will show the latest research outcomes in hadron spectroscopy, including searches for the hidden bottom transitions between $\Upsilon(10753)$ and bottomonia, measurements of the energy dependence of the $e^{+}e^{-} \rightarrow B^{(*)}\bar{B}^{(*)}$ cross-section, and lifetime measurements of charmed hadrons. The talk also covers recent results from the Belle experiment, which ended operation in 2010. Notably, we will reveal a threshold cusp observed at the $\Lambda\eta$ threshold in the $pK^{-}$ system and new $\Lambda\pi$ signals observed near the $\bar{K}N$ mass threshold in the $\Lambda_{c}^{+}$ decays. 000003909 8560_ $$fsbyang@korea.ac.kr 000003909 8564_ $$uhttps://docs.belle2.org/record/3909/files/BELLE2-TALK-CONF-2023-154.pdf 000003909 8564_ $$uhttps://docs.belle2.org/record/3909/files/BELLE2-TALK-CONF-2023-154_revised.pdf$$yrevised_version