Letter
Open Access

Search for $h_{b} (2 P) \to γ χ_{b J} (1 P)$ at $\sqrt{s} = 10.860 GeV$

A. Boschetti , R. Mussa , U. Tamponi , I. Adachi , H. Aihara , D. M. Asner , T. Aushev , R. Ayad , Sw. Banerjee et al. (Belle Collaboration)

Sw. Banerjee , K. Belous , J. Bennett , M. Bessner , D. Biswas , A. Bobrov , D. Bodrov , A. Bozek , M. Bračko , P. Branchini , T. E. Browder , A. Budano , M.-C. Chang , B. G. Cheon , K. Chilikin , K. Cho , S.-K. Choi , Y. Choi , S. Choudhury , G. De Nardo , G. De Pietro , R. Dhamija , F. Di Capua , Z. Doležal , T. V. Dong , P. Ecker , D. Epifanov , D. Ferlewicz , B. G. Fulsom , R. Garg , V. Gaur , A. Garmash , A. Giri , P. Goldenzweig , E. Graziani , T. Gu , Y. Guan , K. Gudkova , C. Hadjivasiliou , T. Hara , K. Hayasaka , H. Hayashii , S. Hazra , W.-S. Hou , C.-L. Hsu , K. Inami , N. Ipsita , R. Itoh , M. Iwasaki , W. W. Jacobs , Y. Jin , T. Kawasaki , C. Kiesling , C. H. Kim , D. Y. Kim , K.-H. Kim , Y.-K. Kim , K. Kinoshita , P. Kodyš , S. Korpar , E. Kovalenko , P. Križan , P. Krokovny , R. Kumar , K. Kumara , Y.-J. Kwon , T. Lam , D. Levit , L. K. Li , Y. B. Li , L. Li Gioi , D. Liventsev , Y. Ma , M. Masuda , T. Matsuda , D. Matvienko , F. Meier , M. Merola , K. Miyabayashi , R. Mizuk , G. B. Mohanty , M. Nakao , Z. Natkaniec , A. Natochii , L. Nayak , M. Nayak , S. Nishida , S. Ogawa , H. Ono , G. Pakhlova , J. Park , S.-H. Park , A. Passeri , S. Patra , S. Paul , T. K. Pedlar , R. Pestotnik , L. E. Piilonen , T. Podobnik , E. Prencipe , M. T. Prim , N. Rout , G. Russo , S. Sandilya , L. Santelj , V. Savinov , G. Schnell , C. Schwanda , Y. Seino , K. Senyo , W. Shan , C. P. Shen , J.-G. Shiu , A. Sokolov , E. Solovieva , M. Starič , M. Sumihama , M. Takizawa , K. Tanida , F. Tenchini , R. Tiwary , M. Uchida , Y. Unno , S. Uno , A. Vinokurova , E. Wang , M.-Z. Wang , X. L. Wang , E. Won , B. D. Yabsley , J. Yelton , J. H. Yin , Y. Yook , and L. Yuan (Belle Collaboration)

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Phys. Rev. D 111, L011102 – Published 8 January, 2025

DOI: https://doi.org/10.1103/PhysRevD.111.L011102

Abstract

In the bottomonium sector, the hindered magnetic dipole transitions between P-wave states $h_{b} (2 P) \to χ_{b J} (1 P) γ$ , $J = 0$ , 1, 2, are expected to be severely suppressed according to the relativized quark model, due to the spin flip of the $b$ quark. Nevertheless, a recent model following the coupled-channel approach predicts the corresponding branching fractions to be enhanced by orders of magnitude. In this Letter, we report the first search for such transitions. We find no significant signals and set upper limits at 90% confidence level on the corresponding branching fractions: $B [h_{b} (2 P) \to γ χ_{b 0} (1 P)] < 2.7 \times 10^{- 1}$ , $B [h_{b} (2 P) \to γ χ_{b 1} (1 P)] < 5.4 \times 10^{- 3}$ and $B [h_{b} (2 P) \to γ χ_{b 2} (1 P)] < 1.3 \times 10^{- 2}$ . These values help to constrain the parameters of the coupled-channel models. The results are obtained using a $121.4 {fb}^{- 1}$ data sample taken around $\sqrt{s} = 10.860 GeV$ with the Belle detector at the KEKB asymmetric-energy $e^{+} e^{-}$ collider.

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Phys. Rev. D 111, L011102– Published 8 January, 2025

Vol. 111, Iss. 1 — 1 January 2025

Received 5 November 2024
Accepted 10 December 2024

DOI: https://doi.org/10.1103/PhysRevD.111.L011102

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Search for $h_{b} (2 P) \to γ χ_{b J} (1 P)$ at $\sqrt{s} = 10.860 GeV$

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Search for hb(2P)→γχbJ(1P) at s=10.860 GeV

Abstract

Physics Subject Headings (PhySH)

Article Text

References (20)

Search for $h_{b} (2 P) \to γ χ_{b J} (1 P)$ at $\sqrt{s} = 10.860 GeV$