arXiv · 2112.11852
Search for a light Higgs boson in single-photon decays of $\Upsilon(1S)$ using $\Upsilon(2S) \to \pi^+ \pi^- \Upsilon(1S)$ tagging method
Abstract
We search for a light Higgs boson ($A^0$) decaying into a $\tau^+\tau^-$ or $\mu^+\mu^-$ pair in the radiative decays of $\Upsilon(1S)$. The production of $\Upsilon(1S)$ mesons is tagged by $\Upsilon(2S)\to \pi^+ \pi^- \Upsilon(1S)$ transitions, using 158 million $\Upsilon(2S)$ events accumulated with the Belle detector at the KEKB asymmetric energy electron-positron collider. No significant $A^0$ signals in the mass range from the $\tau^+\tau^-$ or $\mu^+\mu^-$ threshold to 9.2 GeV/$c^2$ are observed. We set the upper limits at 90\% credibility level (C.L.) on the product branching fractions for $\Upsilon(1S)\to \gamma A^0$ and $A^0\to \tau^+\tau^-$ varying from $3.8\times10^{-6}$ to $1.5\times10^{-4}$. Our results represent an approximately twofold improvement on the current world best upper limits for the $\Upsilon(1S)\to \gamma A^0(\to \tau^+\tau^-)$ production. For $A^0\to \mu^+\mu^-$, the upper limits on the product branching fractions for $\Upsilon(1S)\to \gamma A^0$ and $A^0\to \mu^+\mu^-$ are at the same level as the world average limits, and vary from $3.1\times10^{-7}$ to $1.6\times10^{-5}$. The upper limits at 90\% C.L. on the Yukawa coupling $f_{\Upsilon(1S)}$ and mixing angle ${\rm sin}\theta_{A^0}$ are also given.
Explore related subjects
Keep this discovery
Belle Collaboration, S. Jia, C. P. Shen, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, P. Behera, K. Belous, J. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka, A. Bobrov, D. Bodrov, G. Bonvicini, J. Borah, M. Bračko, P. Branchini, T. E. Browder, A. Budano, M. Campajola, D. Červenkov, M. -C. Chang, P. Chang, V. Chekelian, A. Chen, B. G. Cheon, K. Chilikin, H. E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, Y. Choi, S. Choudhury, D. Cinabro, S. Cunliffe, S. Das, N. Dash, G. De Nardo, G. De Pietro, R. Dhamija, F. Di Capua, Z. Doležal, T. V. Dong, D. Epifanov, T. Ferber, D. Ferlewicz, B. G. Fulsom, R. Garg, V. Gaur, N. Gabyshev, A. Giri, P. Goldenzweig, B. Golob, E. Graziani, Y. Guan, K. Gudkova, C. Hadjivasiliou, T. Hara, K. Hayasaka, H. Hayashii, M. T. Hedges, W. -S. Hou, K. Inami, G. Inguglia, A. Ishikawa, R. Itoh, M. Iwasaki, Y. Iwasaki, W. W. Jacobs, E. -J. Jang, Y. Jin, K. K. Joo, J. Kahn, A. B. Kaliyar, K. H. Kang, T. Kawasaki, C. Kiesling, C. H. Kim, D. Y. Kim, K. -H. Kim, Y. -K. Kim, K. Kinoshita, P. Kodyš, S. Kohani, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, P. Križan, R. Kroeger, P. Krokovny, M. Kumar, R. Kumar. 2021-12-22. Search for a light Higgs boson in single-photon decays of $\Upsilon(1S)$ using $\Upsilon(2S) \to \pi^+ \pi^- \Upsilon(1S)$ tagging method. https://doi.org/10.1103/physrevlett.128.081804
Cite the original work for its findings. Save a collection to share your selection of sources.