The Belle II experiment at the SuperKEKB energy-asymmetric e+e− collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. The design luminosity of the machine is 6×1035 cm−2s−1 and the Belle II experiment aims to ultimately record 50 ab−1 of data, a factor of 50 more than its predecessor. With this data set, Belle II will be able to measure the...
Less explored from both the theoretical and the experimental sides are the B-meson semileptonic transitions to the lowest lying excited charmed mesons. An accurate knowledge of the form factors of these transitions is important to understand the problem of filling the gap between the inclusive $B \to X_c \ell \bar\nu_\ell $ width and the sum of the exclusive semileptonic widths. These...
The charmoniumlike state ψ(4230)1 is now widely considered as predominantly a D1 ̄D hadronic molecule. The heavy quark spin symmetry (HQSS) thus implies the possible emergence of its heavy quark spin partners with molecular configuration as D1 ̄D∗ and D∗ 2 ̄D∗ below these charmed mesons’ thresholds. Similar heavy quark spin patterns are already identified for instance for recently observed...
