Observation of B (s)0 →j/ψp p Decays and Precision Measurements of the B (s)0 Masses

Academic Article


  • © 2019 CERN, for the LHCb Collaboration. American Physical Society. The first observation of the decays B(s)0→J/ψpp is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2 fb-1, collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are B(B0→J/ψpp)=[4.51±0.40(stat)±0.44(syst)]×10-7, B(Bs0→J/ψpp)=[3.58±0.19(stat)±0.39(syst)]×10-6. For the Bs0 meson, the result is much higher than the expected value of O(10-9). The small available phase space in these decays also allows for the most precise single measurement of both the B0 mass as 5279.74±0.30(stat)±0.10(syst) MeV and the Bs0 mass as 5366.85±0.19(stat)±0.13(syst) MeV.
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    Author List

  • Aaij R; Abellán Beteta C; Adeva B; Adinolfi M; Aidala CA; Ajaltouni Z; Akar S; Albicocco P; Albrecht J; Alessio F
  • Volume

  • 122
  • Issue

  • 19