Status and Prospects of Exotic Hadrons at Belle II

Abstract

In the past twenty years, many new hadrons that are difficult to be explained within the conventional quark model have been discovered in the quarkonium region, which are called exotic hadrons. Belle II experiment, as the next-generation $B$ factory, provides a good platform to explore them. The charmonium-like states can be produced at Belle II in several ways, such as $B$ meson decays, initial-state radiation processes, two-photon collisions, and double charmonium productions. The bottomonium-like states can be produced directly in $e^{+}{e}^{-}$ colliding energies at Belle II with low continuum backgrounds. Belle II plans to perform a high-statistics energy scan from the $B\bar{B}$ threshold up to the highest possible energy of 11.24 GeV to search for new $Y_b$ states with $J^{PC}$ = $1^{--}$, $X_b$ (the bottom counterpart of ${\chi }_{c1}(3872)$ (also known as $X(3872)$)), and partners of $Z_b$ states. In this paper, we give a mini-review on the status and prospects of exotic hadrons at Belle II.

arXiv comment7 pages, 5 figures

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• Photon-induced production of the exotic charged charmonium-like state $Z_c(3900)$ off nuclear targets and its internal structure
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