Search for a dark leptophilic scalar produced in association with ${\tau }^{+}{\tau }^{-}$ pair in $e^{+}{e}^{-}$ annihilation at center-of-mass energies near 10.58 GeV

Journal Article · Mon Feb 05 00:00:00 EST 2024 · Physical Review. D.

DOI:https://doi.org/10.1103/PhysRevD.109.032002· OSTI ID:2474068

Biswas, D.; Banerjee, Sw.; Adachi, I.; Aihara, H.; Asner, D. M.; Aushev, T.; Ayad, R.; Babu, V.; Behera, P.; Bennett, J.; Bessner, M.; Bhardwaj, V.; Bhuyan, B.; Bilka, T.; Bodrov, D.; Borah, J.; Bozek, A.; Bračko, M.; Branchini, P.; Browder, T. E. ; Budano, A.; Campajola, M.; Červenkov, D.; Chang, M. -C.; Chang, P.; Cheon, B. G.; Chilikin, K.; Cho, H. E.; Cho, K.; Choi, S. -K.; Choi, Y.; Choudhury, S.; Cinabro, D.; Das, S.; De Nardo, G.; De Pietro, G.; Dhamija, R.; Di Capua, F.; Dingfelder, J.; Doležal, Z.; Dong, T. V.; Dubey, S.; Ecker, P.; Epifanov, D.; Ferber, T.; Fulsom, B. G.; Gaur, V.; Garmash, A.; Giri, A.; Goldenzweig, P.; Graziani, E.; Guan, Y.; Gudkova, K.; Hadjivasiliou, C.; Hayasaka, K.; Hayashii, H.; Hazra, S.; Hedges, M. T.; Herrmann, D.; Hernández Villanueva, M.; Hou, W. -S.; Hsu, C. -L.; Inami, K.; Inguglia, G.; Ipsita, N.; Ishikawa, A.; Itoh, R.; Iwasaki, M.; Jacobs, W. W.; Ji, Q. P.; Jia, S.; Jin, Y.; Joo, K. K.; Kaliyar, A. B.; Kiesling, C.; Kim, C. H.; Kim, D. Y.; Kim, K. -H.; Kim, Y. J.; Kim, Y. -K.; Kodyš, P.; Konno, T.; Korobov, A.; Korpar, S.; Križan, P.; Krokovny, P.; Kumar, M.; Kumara, K.; Kwon, Y. -J.; Lai, Y. -T.; Laurenza, M.; Lee, S. C.; Levit, D.; Li, J.; Li, L. K.; Li, Y.; Li Gioi, L.; Libby, J.; Lieret, K.; Lin, Y. -R.; Liventsev, D.; Luo, T.; Ma, Y.; Masuda, M.; Maurya, S. K.; Meier, F.; Merola, M.; Metzner, F.; Miyabayashi, K.; Mizuk, R.; Nakamura, I.; Nakao, M.; Natkaniec, Z.; Natochii, A.; Nayak, L.; Niiyama, M.; Nisar, N. K.; Nishida, S.; Ogawa, S.; Ono, H.; Pakhlov, P.; Pakhlova, G.; Pardi, S.; Park, H.; Park, J.; Park, S. -H.; Passeri, A.; Patra, S.; Paul, S.; 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.; Sevior, M. E.; Shan, W.; Sharma, C.; Shiu, J. -G.; Shwartz, B.; Singh, J. B.; Sokolov, A.; Solovieva, E.; Starič, M.; Stottler, Z. S.; Sumihama, M.; Takizawa, M.; Tanida, K.; Tenchini, F.; Trabelsi, K.; Uchida, M.; Uglov, T.; Unno, Y.; Uno, K.; Uno, S.; Urquijo, P.; Vinokurova, A.; Wang, D.; Wang, E.; Watanuki, S.; Won, E.; Xu, X.; Yabsley, B. D.; Yan, W.; Yin, J. H.; Yuan, C. Z.; Yuan, L.; Zhang, Z. P.; Zhilich, V.; Zhukova, V.; Zhulanov, V.

A dark leptophilic scalar $\left({\varphi }_L\right)$ is a hypothetical particle that couples only to leptons rather than quarks. We report on a search for ${\varphi }_L$ in the $e^{+}{e}^{-}\to {\tau }^{+}{\tau }^{-}{\varphi }_L$ , ${\varphi }_L\to {\ell }^{+}{\ell }^{-}(\ell =e,\mu )$ process using $626{\mathrm{fb}}^{-1}$ of data collected by the Belle experiment near the $\mathrm{\Upsilon }\left(4S\right)$ resonance. We validate the backgrounds with multiple control regions in data, using a novel multiclass multivariate event classifier. In absence of a signal, we quote upper limits at the 90% confidence level on the coupling between ${\varphi }_L$ and leptons. Our bounds, obtained in a blinded approach, are 19% more constraining than the previous limits, averaged over the mass range $0.04\le m_{{\varphi }_L}\le 6.5\mathrm{GeV}$ . We exclude the parameter space below 4 GeV favored by measurement of the anomalous magnetic moment of the muon.

Published by the American Physical Society 2024

• Sponsoring Organization: USDOE
• OSTI ID: 2474068
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 3 Vol. 109; ISSN PRVDAQ; ISSN 2470-0010
• Publisher: American Physical Society
• Country of Publication: United States
• Language: English