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arXiv · 2606.23170

Recent Hadron Spectroscopy Results from the Belle and Belle II experiments

Elisabetta Prencipe
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Abstract

The Belle~II experiment, the major upgrade of the Belle detector, is currently collecting data at the SuperKEKB asymmetric-energy $e^+e^-$ collider in Tsukuba, Japan. With an integrated luminosity of 575\,fb$^{-1}$, Belle~II has already surpassed the maximum luminosity accumulated by both BaBar and Belle. Recent analyses combining Belle and Belle~II data sets have delivered results of unprecedented precision, demonstrating the strong potential of the unified data sample, which now exceeds 1.5\,ab$^{-1}$. In this contribution, recent advances in hadron spectroscopy are presented. Highlights include new results in bottomonium and charmonium physics, with particular emphasis on the structure of the $\Upsilon(10753)$, searches for hidden-charm and hidden-strangeness pentaquarks, and the latest developments in baryon spectroscopy, including studies of the $\Omega(2012)$ and excited $\Lambda_c$ states. Prospects for future spectroscopy analyses exploiting the full Belle and Belle~II data sets are also discussed.

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Elisabetta Prencipe. 2026-06-22. Recent Hadron Spectroscopy Results from the Belle and Belle II experiments. https://arxiv.org/abs/2606.23170

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