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

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 $e^{+}{e}^{-}\to ({\pi }^{+}{\pi }^{-}{\pi }^0{)}_{\mathrm{non}-\omega }{\chi }_{b1}$ and first evidence for $e^{+}{e}^{-}\to \omega {\chi }_{bJ}$ in the vicinity of the ${\rm Y}(11020)$ resonance, with center-of-mass energies from 10.96 to 11.05~GeV. The significances for $({\pi }^{+}{\pi }^{-}{\pi }^0{)}_{\mathrm{non}-\omega }{\chi }_{b1}$ 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 ${\rm Y}(10860)$ and ${\rm Y}(11020)$ resonances or non-resonant 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.

8pages, 3 figures

References in corpus (8)

• Observation of anomalous Upsilon(1S)pi+pi- and Upsilon(2S)pi+pi- production near the Upsilon(5S) resonance
• Amplitude analysis of e+e- => Y(nS)pi+pi- at sqrt(s)=10.865 GeV
• Observation of $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}{\pi }^0{\chi }_{bJ}$ and search for $X_b\to \omega {\rm Y}(1S)$ at $\sqrt{s}\sim 10.867$ GeV
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• Explaining the anomalous ${\rm Y}(5S)\to {\chi }_{bJ}\omega$ decays through the hadronic loop effect
• Enhanced breaking of heavy quark spin symmetry
• Exploring the ${\rm Y}(6S)\to {\chi }_{bJ}\varphi$ and ${\rm Y}(6S)\to {\chi }_{bJ}\omega$ hidden-bottom hadronic transitions
• Contribution of $Z_b$ resonances to ${\rm Y}(5S)\to \pi \pi \pi {\chi }_b$

Cited by in corpus (2)

• $D$ wave bottomonia production from $Z_b^{(\prime )}$ decay
• Search for $h_b(2P)\to \gamma {\chi }_{bJ}(1P)$ at $\sqrt{s}=10.860$ GeV