Search for $h_b\left(2P\right)\to \gamma {\chi }_{bJ}\left(1P\right)$ at $\sqrt{s}=10.860\mathrm{GeV}$

Journal Article · 07 January 2025 · Physical Review. D.

DOI: https://doi.org/10.1103/PhysRevD.111.L011102 · OSTI ID:2497370

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

In the bottomonium sector, the hindered magnetic dipole transitions between P-wave states $h_b\left(2P\right)\to {\chi }_{bJ}\left(1P\right)\gamma$ , $J=0$ , 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: $\mathcal{B}\left[h_b\right(2P)\to \gamma {\chi }_{b0}(1P\left)\right]<2.7\times {10}^{-1}$ , $\mathcal{B}\left[h_b\right(2P)\to \gamma {\chi }_{b1}(1P\left)\right]<5.4\times {10}^{-3}$ and $\mathcal{B}\left[h_b\right(2P)\to \gamma {\chi }_{b2}(1P\left)\right]<1.3\times {10}^{-2}$ . These values help to constrain the parameters of the coupled-channel models. The results are obtained using a $121.4{\mathrm{fb}}^{-1}$ data sample taken around $\sqrt{s}=10.860\mathrm{GeV}$ with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. Published by the American Physical Society 2025

• Sponsoring Organization: USDOE
• OSTI ID: 2497370
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 1 Vol. 111; ISSN PRVDAQ; ISSN 2470-0010
• Publisher: American Physical SocietyCopyright Statement
• Country of Publication: United States
• Language: English