# Observation of ${e}^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}{\pi }^{0}{\chi }_{b1,2}\left(1P\right)$ and search for ${e}^{+}{e}^{-}\to \varphi {\chi }_{b1,2}\left(1P\right)$ at $\sqrt{s}=10.96—11.05\text{}\text{}\mathrm{GeV}$

15 November 2018

Abstract: We report searches for the processes ${e}^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}{\pi }^{0}{\chi }_{bJ}$ and ${e}^{+}{e}^{-}\to \varphi {\chi }_{bJ}$ ($J=1$, 2) based on data samples collected by the Belle experiment at the KEKB collider. We report the first observation of the process ${e}^{+}{e}^{-}\to \left({\pi }^{+}{\pi }^{-}{\pi }^{0}{\right)}_{\mathrm{non}-\omega }{\chi }_{b1}$ and first evidence for ${e}^{+}{e}^{-}\to \omega {\chi }_{bJ}$ in the vicinity of the $\Upsilon \left(11020\right)$ resonance, with center-of-mass energies from 10.96 to 11.05 GeV. The significances for $\left({\pi }^{+}{\pi }^{-}{\pi }^{0}{\right)}_{\mathrm{non}-\omega }{\chi }_{b1}$ and $\omega {\chi }_{bJ}$ are greater than $5.3\sigma$ and $4.0\sigma$, respectively. We also investigate the energy dependence of the ${e}^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}{\pi }^{0}{\chi }_{bJ}$ cross section, but we cannot determine whether the contributions are from the $\Upsilon \left(10860\right)$ and $\Upsilon \left(11020\right)$ resonances or nonresonant continuum processes. The signals for ${e}^{+}{e}^{-}\to \varphi {\chi }_{bJ}$ are not significant, and the upper limits of the Born cross sections at the 90% confidence level are 0.7 and 1.0 pb for ${e}^{+}{e}^{-}\to \varphi {\chi }_{b1}$ and $\varphi {\chi }_{b2}$, respectively, for center-of-mass energies from 10.96 to 11.05 GeV.

Published in: Physical Review D 98 (2018)
DOI: 10.1103/PhysRevD.98.091102
arXiv: 1806.06203

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