Journal article

Search for B- -> mu(-)(nu)over-bar(mu) Decays at the Belle Experiment

A Sibidanov, KE Varvell, I Adachi, H Aihara, S Al Said, DM Asner, T Aushev, R Ayad, V Babu, I Badhrees, S Bahinipati, AM Bakich, V Bansal, E Barberio, P Behera, B Bhuyan, J Biswal, A Bozek, M Bracko, TE Browder Show all

Physical Review Letters | American Physical Society | Published : 2018

Abstract

We report the results of a search for the rare, purely leptonic decay B−→μ−¯νμ performed with a 711  fb−1 data sample that contains 772×106  B¯B pairs, collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B−→μ−¯νμ)=(6.46±2.22±..

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Grants

Awarded by Australian Research Council


Awarded by Austrian Science Fund


Awarded by National Natural Science Foundation of China


Awarded by Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS)


Awarded by Fudan University


Awarded by Ministry of Education, Youth and Sports of the Czech Republic


Awarded by National Research Foundation (NRF) of Korea


Awarded by Ikerbasque, Basque Foundation for Science, Basque Government


Funding Acknowledgements

We thank the KEKB group for the excellent operation of the accelerator; the KEK cryogenics group for the efficient operation of the solenoid; and the KEK computer group, the National Institute of Informatics, and the Pacific Northwest National Laboratory (PNNL) Environmental Molecular Sciences Laboratory (EMSL) computing group for valuable computing and Science Information NETwork 5 (SINET5) network support. We acknowledge support from the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan, the Japan Society for the Promotion of Science (JSPS), and the Tau-Lepton Physics Research Center of Nagoya University; the Australian Research Council including Grants No. DP180102629, No. DP170102389, No. DP170102204, No. DP150103061, No. FT130100303; Austrian Science Fund under Grant No. P 26794-N20; the National Natural Science Foundation of China under Contracts No. 11435013, No. 11475187, No. 11521505, No. 11575017, No. 11675166, No. 11705209; Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS), Grant No. QYZDJ-SSW-SLH011; the CAS Center for Excellence in Particle Physics (CCEPP); Fudan University Grants No. JIH5913023, No. IDH5913011/003, No. JIH5913024, No. IDH5913011/002; the Ministry of Education, Youth and Sports of the Czech Republic under Contract No. LTT17020; the Carl Zeiss Foundation, the Deutsche Forschungsgemeinschaft, the Excellence Cluster Universe, and the VolkswagenStiftung; the Department of Science and Technology of India; the Istituto Nazionale di Fisica Nucleare of Italy; National Research Foundation (NRF) of Korea Grants No. 2014R1A2A2A01005286, No. 2015R1A2A2A01003280, No. 2015H1A2A1033649, No. 2016R1D1A1B01010135, No. 2016K1A3A7A09005603, and No. 2016R1D1A1B02012900; Radiation Science Research Institute, Foreign Large-size Research Facility Application Supporting project and the Global Science Experimental Data Hub Center of the Korea Institute of Science and Technology Information; the Polish Ministry of Science and Higher Education and the National Science Center; the Ministry of Education and Science of the Russian Federation and the Russian Foundation for Basic Research; the Slovenian Research Agency; Ikerbasque, Basque Foundation for Science, Basque Government (No. IT956-16) and Ministry of Economy and Competitiveness (MINECO) (Juan de la Cierva), Spain; the Swiss National Science Foundation; the Ministry of Education and the Ministry of Science and Technology of Taiwan; and the United States Department of Energy and the National Science Foundation.