LHCb CollaborationAdeva Andany, BernardoDosil Suárez, ÁlvaroFernández Albor, Víctor ManuelGallas Torreira, Abraham AntonioGarcía Pardiñas, JuliánHernando Morata, José ÁngelLucio Martínez, MiriamMartínez Santos, DiegoPlo Casasus, MáximoRomero Vidal, AntonioSaborido Silva, Juan JoséSanmartín Sedes, BraisSantamarina Ríos, CibránVázquez Regueiro, PabloVázquez Sierra, CarlosVieites Díaz, María2020-04-242020-04-242015Aaij, R., Adeva, B., Adinolfi, M. et al. Measurement of the B 0s → ϕϕ branching fraction and search for the decay B 0 → ϕϕ . J. High Energ. Phys. 2015, 53 (2015). https://doi.org/10.1007/JHEP10(2015)053http://hdl.handle.net/10347/21694Using a dataset corresponding to an integrated luminosity of 3.0 fb−1 collected in pp collisions at centre-of-mass energies of 7 and 8 TeV, the B 0s → ϕϕ branching fraction is measured to be B(B0s→ϕϕ)=(1.84±0.05(stat)±0.07(syst)±0.11(fs/fd)±0.12(norm))×10−5, where f s /f d represents the ratio of the B 0s to B 0 production cross-sections, and the B 0 → ϕK *(892)0 decay mode is used for normalization. This is the most precise measurement of this branching fraction to date, representing a factor five reduction in the statistical uncertainty compared with the previous best measurement. A search for the decay B 0 → ϕϕ is also made. No signal is observed, and an upper limit on the branching fraction is set as B(B0→ϕϕ)<2.8×10−8 at 90% confidence level. This is a factor of seven improvement compared to the previous best limit.eng© CERN, for the benefit of the LHCb Collaboration. Article funded by SCOAP3. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0), which permits use, duplication, adaptation, distribution, and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were madehttps://creativecommons.org/licenses/by/4.0Hadron-hadron scatteringBranching fractionB physicsFlavor physicsjournal article10.1007/JHEP10(2015)0531029-8479open access