1. Search for B⁺→K⁺ν$\bar{ν}$ Decays Using an Inclusive Tagging Method at Belle II
- Author
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Belle 2 Collaboration, Abudinén, F., Adachi, I., Adamczyk, K., Ahlburg, P., Aihara, H., Akopov, N., Aloisio, A., Anh Ky, N., Asner, D. M., Atmacan, H., Aushev, T., Aushev, V., Baur, A., Babu, V., Baehr, S., Bambade, P., Banerjee, Sw., Bansal, S., Baudot, J., Becker, J., Behera, P. K., Bennett, J. V., Bernieri, E., Bernlochner, F. U., Bertemes, M., Bertholet, E., Bessner, M., Bettarini, S., Bianchi, F., Bilka, T., Biswas, D., Bozek, A., Bračko, M., Branchini, P., Braun, N., Browder, T. E., Budano, A., Bussino, S., Campajola, M., Cao, L., Casarosa, G., Cecchi, C., Červenkov, D., Chang, P., Cheaib, R., Chekelian, V., Chen, C., Chen, Y.-T., Cheon, B. G., Chilikin, K., Chirapatpimol, K., Cho, K., Cho, S.-J., Choudhury, S., Cinabro, D., Corona, L., Cremaldi, L. M., Cunliffe, S., Czank, T., Dattola, F., De La Cruz-Burelo, E., Marino, G. de, De Nardo, G., De Nuccio, M., De Pietro, G., Sangro, R. de, Destefanis, M., Dey, S., De Yta-Hernandez, A., Di Canto, A., Di Capua, F., Dingfelder, J., Doležal, Z., Domínguez Jiménez, I., Dong, T. V., Dort, K., Dubey, S., Duell, S., Dujany, G., Eidelman, S., Eliachevitch, M., Epifanov, D., Ferber, T., Ferlewicz, D., Fillinger, T., Finocchiaro, G., Fiore, S., Fodor, A., Forti, F., Frey, A., Fulsom, B. G., Gabyshev, N., Ganiev, E., Garcia-Hernandez, M., Garmash, A., Gaur, V., Gaz, A., Gellrich, A., Giordano, R., Giri, A., Glazov, A., Gobbo, B., Godang, R., Goldenzweig, P., Golob, B., Grace, P., Gradl, W., Graziani, E., Greenwald, D., Guan, Y., Gudkova, K., Hadjivasiliou, C., Halder, S., Hara, K., Hartbrich, O., Hayasaka, K., Hayashii, H., Hazra, S., Hearty, C., Heredia de la Cruz, I., Hernández Villanueva, M., Hershenhorn, A., Higuchi, T., Hill, E. C., Hirata, H., Hoek, M., Hohmann, M., Hsu, C.-L., Humair, T., Iijima, T., Inami, K., Inguglia, G., Irakkathil Jabbar, J., Ishikawa, A., Itoh, R., Iwasaki, M., Iwasaki, Y., Jackson, P., Jacobs, W. W., Jaffe, D. E., Jin, Y., Joo, C., Junkerkalefeld, H., Kaliyar, A. B., Kandra, J., Kang, K. H., Karl, R., Karyan, G., Kawasaki, T., Ketter, C., Kichimi, H., Kiesling, C., Kim, C.-H., Kim, D. Y., Kim, Y.-K., Kimmel, T. D., Kodyš, P., Koga, T., Kohani, S., Konno, T., Korobov, A., Korpar, S., Kovalenko, E., Kraetzschmar, T. M. G., Krinner, F., Križan, P., Krokovny, P., Kuhr, T., Kumar, J., Kumar, M., Kumar, R., Kumara, K., Kunigo, T., Kurz, S., Kuzmin, A., Kwon, Y.-J., Lacaprara, S., Lai, Y.-T., La Licata, C., Lanceri, L., Lange, J. S., Laurenza, M., Lautenbach, K., Le Diberder, F. R., Lee, S. C., Leitl, P., Levit, D., Lewis, P. M., Li, C., Li, L. K., Li, S. X., Li, Y. B., Libby, J., Lieret, K., Liptak, Z., Liu, Q. Y., Liventsev, D., Longo, S., Lozar, A., Lueck, T., Lyu, C., Maggiora, M., Maity, S., Manfredi, R., Manoni, E., Marcello, S., Marinas, C., Martini, A., Masuda, M., Matsuda, T., Matsuoka, K., Matvienko, D., Meier, F., Merola, M., Metzner, F., Milesi, M., Miller, C., Miyabayashi, K., Miyake, H., Mizuk, R., Mohanty, G. B., Moser, H.-G., Mrvar, M., Müller, F. J., Murphy, C., Mussa, R., Nakamura, K. R., Nakao, M., Natkaniec, Z., Natochii, A., Nayak, M., Nazaryan, G., Niebuhr, C., Nisar, N. K., Nishida, S., Nishimura, K., Ogawa, S., Onishchuk, Y., Ono, H., Onuki, Y., Oskin, P., Ozaki, H., Pakhlov, P., Pakhlova, G., Paladino, A., Pang, T., Panta, A., Paoloni, E., Pardi, S., Park, H., Park, S.-H., Paschen, B., Passeri, A., Pathak, A., Patra, S., Paul, S., Pedlar, T. K., Peruzzi, I., Pestotnik, R., Piccolo, M., Piilonen, L. E., Podesta-Lerma, P. L. M., Podobnik, T., Pokharel, S., Polat, G., Popov, V., Praz, C., Prell, S., Prencipe, E., Prim, M. T., Rad, N., Rados, P., Raiz, S., Remnev, M., Ripp-Baudot, I., Ritter, M., Rizzo, G., Rizzuto, L. B., Robertson, S. H., Rodríguez Pérez, D., Roney, J. M., Rostomyan, A., Rout, N., Russo, G., Sahoo, D., Sanders, D. A., Sandilya, S., Sangal, A., Santelj, L., Sato, Y., Savinov, V., Scavino, B., Schueler, J., Schwanda, C., Schwartz, A. J., Seddon, R. M., Seino, Y., Selce, A., Senyo, K., Serrano, J., Sevior, M. E., Sfienti, C., Shiu, J.-G., Shwartz, B., Sibidanov, A., Simon, F., Sobie, R. J., Soffer, A., Sokolov, A., Solovieva, E., Spataro, S., Spruck, B., Starič, M., Stefkova, S., Stottler, Z. S., Stroili, R., Sumihama, M., Sumisawa, K., Summers, D. J., Sutcliffe, W., Suzuki, S. Y., Svidras, H., Tabata, M., Takahashi, M., Takizawa, M., Tamponi, U., Tanaka, S., Tanida, K., Tanigawa, H., Taniguchi, N., Taras, P., Tenchini, F., Tonelli, D., Torassa, E., Toutounji, N., Trabelsi, K., Uchida, M., Unno, Y., Uno, K., Uno, S., Urquijo, P., Ushiroda, Y., Usov, Y. V., Vahsen, S. E., Tonder, R. van, Varner, G. S., Varvell, K. E., Vinokurova, A., Vitale, L., Wach, B., Waheed, E., Wakeling, H. M., Wan Abdullah, W., Wang, M.-Z., Wang, X. L., Warburton, A., Watanuki, S., Webb, J., Welsch, M., Wessel, C., Wiechczynski, J., Windel, H., Xu, X. P., Yabsley, B. D., Yamada, S., Yan, W., Yang, S. B., Ye, H., Yelton, J., Yin, J. H., Yook, Y. M., Yoshihara, K., Yuan, C. Z., Yusa, Y., Zani, L., Zhilich, V., Zhou, Q. D., Zhou, X. Y., and Zhukova, V. I.
- Subjects
Physics ,High Energy Physics::Experiment ,ddc:530 - Abstract
A search for the flavor-changing neutral-current decay B$^{+}$→K$^{+}$ν$\overline{ν}$ is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63 fb$^{-1}$ collected at the Υ(4S) resonance and a sample of 9 fb$^{-1}$ collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B$^{+}$→K+ν¯ν decay, but also the inclusive properties of the other B meson in the Υ(4S)→B$\overline{B}$ event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B$^{+}$→K$^{+}$ν$\overline{ν}$ of 4.1×10$^{-5}$ is set at the 90% confidence level.
- Published
- 2021