Search for the $e^{+}{e}^{-}\to \hat{I}{\cdot }_b(1S)\ddot{I}‰$ and $e^{+}{e}^{-}\to \ddot{I}{‡}_{b0}(1P)\ddot{I}‰$ processes at $\sqrt{s}=10.745\mathrm{GeV}$

Abstract

We search for the $e^{+}{e}^{-}\to \hat{I}{\cdot }_b(1S)\ddot{I}‰$ and $e^{+}{e}^{-}\to \ddot{I}{‡}_{b0}(1P)\ddot{I}‰$ processes at a center-of-mass energy of 10.745 GeV, which is close to the peak of the $\hat{I}\yen (10753)$ state. We use data collected by the Belle II experiment during a special run, corresponding to an integrated luminosity of $9.8{\mathrm{fb}}^{-1}$. We reconstruct $\ddot{I}‰\to \ddot{I}{€}^{+}\ddot{I}{€}^{-}\ddot{I}{€}^0$ decays and use the $\ddot{I}‰$ meson's recoil mass to search for the signals. We do not find evidence for either process, and set upper limits on the corresponding Born-level cross sections of 2.5 pb and 7.8 pb, respectively, at the 90% confidence level. The $\ddot{I}{‡}_{b0}(1P)\ddot{I}‰$ limit is the result of a combination of this analysis and a previous search using full reconstruction.

8 pages, 3 figures, submitted to PRD