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First search for the ηc2(1D) in B decays at Belle

A preprint version of the article is available at arXiv.


The first dedicated search for the ηc2(1D) is carried out using the decays B+ → ηc2(1D)K+, B0ηc2(1D)\( {K}_S^0 \), B0 → ηc2(1D)πK+, and B+ → ηc2(1D)π+\( {K}_S^0 \) with ηc2(1D) → hcγ. No significant signal is found. For the ηc2(1D) mass range between 3795 and 3845 MeV/c2, the branching-fraction upper limits are determined to be ℬ(B+ → ηc2(1D)K+) × ℬ(ηc2(1D) → hcγ) < 3.7 × 105, ℬ(B0 → ηc2(1D)K0) × ℬ(ηc2(1D) → hcγ) < 3.5 × 105, ℬ(B0 → ηc2(1D)πK+) × ℬ(ηc2(1D) → hcγ) < 1.0 × 104, and ℬ(B+ → ηc2(1D)π+\( {K}_S^0 \)) × ℬ(ηc2(1D) → hcγ) < 1.1 × 104 at 90% C.L. The analysis is based on the 711 fb1 data sample collected on the ϒ(4S) resonance by the Belle detector, which operated at the KEKB asymmetric-energy e+e collider.


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Correspondence to K. Chilikin.

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ArXiv ePrint: 2003.08335

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The Belle collaboration., Chilikin, K., Adachi, I. et al. First search for the ηc2(1D) in B decays at Belle. J. High Energ. Phys. 2020, 34 (2020).

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  • e+-e Experiments
  • Quarkonium
  • Spectroscopy