Search for $B^+ \to \mu^+\, \nu_\mu$ and $B^+ \to \mu^+\, N$ with inclusive tagging

Autor: Prim, M. T., Bernlochner, F. U., Goldenzweig, P., Heck, M., Adachi, I., Adamczyk, K., Aihara, H., Said, S. Al, Asner, D. M., Atmacan, H., Aulchenko, V., Aushev, T., Ayad, R., Babu, V., Bakich, A. M., Bansal, V., Behera, P., Beleño, C., Bhardwaj, V., Bhuyan, B., Bilka, T., Biswal, J., Bobrov, A., Bozek, A., Bračko, M., Braun, N., Browder, T. E., Campajola, M., Cao, L., Červenkov, D., Chang, P., Chekelian, V., Chen, A., Cheon, B. G., Chilikin, K., Cho, H. E., Cho, K., Choi, Y., Choudhury, S., Cinabro, D., Cunliffe, S., Doležal, Z., Eidelman, S., Epifanov, D., Fast, J. E., Ferber, T., Fulsom, B. G., Garg, R., Gaur, V., Garmash, A., Giri, A., Grzymkowska, O., Guan, Y., Haba, J., Hara, T., Hayasaka, K., Hayashii, H., Hou, W. -S., Iijima, T., Inami, K., Inguglia, G., Ishikawa, A., Iwasaki, M., Iwasaki, Y., Jia, S., Jin, Y., Joffe, D., Joo, K. K., Kaliyar, A. B., Karyan, G., Kawasaki, T., Kichimi, H., Kiesling, C., Kim, C. H., Kim, D. Y., Kim, K. T., Kim, S. H., Kinoshita, K., Kodyš, P., Korpar, S., Kotchetkov, D., Križan, P., Kroeger, R., Krokovny, P., Kuhr, T., Kulasiri, R., Kumar, R., Kumita, T., Kuzmin, A., Kwon, Y. -J., Lalwani, K., Lange, J. S., Lee, I. S., Lee, J. K., Lee, J. Y., Lee, S. C., Lewis, P., Li, C. H., Gioi, L. Li, Libby, J., Lieret, K., Liventsev, D., Lu, P. -C., Luo, T., MacNaughton, J., Masuda, M., Matsuda, T., Matvienko, D., Merola, M., Metzner, F., Miyabayashi, K., Mizuk, R., Mohanty, G. B., Mussa, R., Nakao, M., De Nardo, G., Nath, K. J., Natkaniec, Z., Nayak, M., Niiyama, M., Nisar, N. K., Nishida, S., Nishimura, K., Ogawa, S., Ono, H., Onuki, Y., Pakhlov, P., Pakhlova, G., Pal, B., Pardi, S., Park, H., Park, S. -H., Patra, S., Paul, S., Pedlar, T. K., Pestotnik, R., Piilonen, L. E., Popov, V., Prencipe, E., Ritter, M., Rostomyan, A., Rozanska, M., Russo, G., Sahoo, D., Sakai, Y., Santelj, L., Savinov, V., Schneider, O., Schnell, G., Schueler, J., Schwanda, C., Seino, Y., Senyo, K., Sevior, M. E., Shebalin, V., Shiu, J. -G., Shwartz, B., Simon, F., Sokolov, A., Solovieva, E., Starič, M., Strube, J. F., Sumihama, M., Sumiyoshi, T., Sutcliffe, W., Takizawa, M., Tamponi, U., Tao, Y., Tenchini, F., Uchida, M., Uglov, T., Unno, Y., Uno, S., Ushiroda, Y., Usov, Y., Vahsen, S. E., Van Tonder, R., Varner, G., Varvell, K. E., Vinokurova, A., Wang, B., Wang, C. H., Wang, M. -Z., Wang, P., Watanuki, S., Won, E., Yang, S. B., Ye, H., Yin, J. H., Yusa, Y., Zhang, Z. P., Zhilich, V., Zhukova, V., Zhulanov, V.
Rok vydání: 2019
Předmět:
Zdroj: Phys. Rev. D 101, 032007 (2020)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevD.101.032007
Popis: We report the result for a search for the leptonic decay of $B^+ \to \mu^+ \, \nu_{\mu}$ using the full Belle data set of 711 fb${}^{-1}$ of integrated luminosity at the $\Upsilon(4S)$ resonance. In the Standard Model leptonic $B$-meson decays are helicity and CKM suppressed. To maximize sensitivity an inclusive tagging approach is used to reconstruct the second $B$ meson produced in the collision. The directional information from this second $B$ meson is used to boost the observed $\mu$ into the signal $B$ meson rest-frame, in which the $\mu$ has a monochromatic momentum spectrum. Though its momentum is smeared by the experimental resolution, this technique improves the analysis sensitivity considerably. Analyzing the $\mu$ momentum spectrum in this frame we find $\mathcal{B}(B^+ \to \mu^+ \, \nu_\mu) = \left( 5.3 \pm 2.0 \pm 0.9 \right) \times 10^{-7}$ with a one-sided significance of 2.8 standard deviations over the background-only hypothesis. This translates to a frequentist upper limit of $\mathcal{B}(B^+ \to \mu^+ \, \nu_{\mu}) < 8.6 \times 10^{-7}$ at 90% CL. The experimental spectrum is then used to search for a massive sterile neutrino, $B^+ \to \mu^+ \, N$, but no evidence is observed for a sterile neutrino with a mass in a range of 0 - 1.5 GeV. The determined $B^+ \to \mu^+ \, \nu_{\mu}$ branching fraction limit is further used to constrain the mass and coupling space of the type II and type III two-Higgs-doublet models.
Databáze: arXiv