Measurement of the branching fraction of the decay B+ →π+π-ℓ+νℓ in fully reconstructed events at Belle

Authors

C. Beleño, Georg-August-Universität Göttingen
A. Frey, Georg-August-Universität Göttingen
I. Adachi, The Graduate University for Advanced Studies
H. Aihara, The University of Tokyo
D. M. Asner, Brookhaven National Laboratory
H. Atmacan, University of Cincinnati
T. Aushev, HSE University
R. Ayad, University of Tabuk
P. Behera, Indian Institute of Technology Madras
J. Bennett, University of Mississippi
F. Bernlochner, Universität Bonn
V. Bhardwaj, Indian Institute of Science Education and Research Mohali
T. Bilka, Charles University
J. Biswal, Jozef Stefan Institute
G. Bonvicini, Wayne State University
A. Bozek, Henryk Niewodniczanski Institute of Nuclear Physics of the Polish Academy of Sciences
M. Bračko, Jozef Stefan Institute
T. E. Browder, University of Hawaiʻi at Mānoa
M. Campajola, Istituto Nazionale di Fisica Nucleare, Sezione di Napoli

Document Type

Article

Publication Date

6-1-2021

Abstract

We present an analysis of the exclusive B+→π+π-ℓ+νℓ decay, where ℓ represents an electron or a muon, with the assumption of charge-conjugation symmetry and lepton universality. The study exploits the full ϒ(4S) data sample collected by the Belle detector, corresponding to 711 fb-1 of integrated luminosity. Events are selected by fully reconstructing one B meson in hadronic decay modes, subsequently determining the properties of the other B meson. We extract the signal yields using a binned maximum-likelihood fit to the missing-mass squared distribution in bins of the invariant mass of the two pions or the momentum transfer squared. We measure a total branching fraction of B(B+→π+π-ℓ+νℓ)=[22.7-1.6+1.9(stat)±3.5(syst)]×10-5, where the uncertainties are statistical and systematic, respectively. This result is the first reported measurement of this decay.

Relational Format

journal article

Recommended Citation

Beleño, C., Frey, A., Adachi, I., Aihara, H., Asner, D. M., Atmacan, H., Aushev, T., Ayad, R., Behera, P., Bennett, J., Bernlochner, F., Bhardwaj, V., Bilka, T., Biswal, J., Bonvicini, G., Bozek, A., Bračko, M., Browder, T. E., Campajola, M., … Belle Collaboration. (2021). Measurement of the branching fraction of the decay B + → π + π − ℓ + ν ℓ in fully reconstructed events at Belle. Physical Review D, 103(11), 112001. https://doi.org/10.1103/PhysRevD.103.112001

DOI

10.1103/PhysRevD.103.112001

Accessibility Status

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