Measurement of the CP-violating phase β in B0→J/ψπ+π- decays and limits on penguin effects

LHCb Collaboration

Research output: Contribution to journalArticle

34 Scopus citations


Time-dependent CP violation is measured in the B(---)0→J/ψπ+π- channel for each π+π- resonant final state using data collected with an integrated luminosity of 3.0 fb-1 in pp collisions using the LHCb detector. The final state with the largest rate, J/ψρ0(770), is used to measure the CP-violating angle 2βeff to be (41.7±9.6-6.3+2.8)°. This result can be used to limit the size of penguin amplitude contributions to CP violation measurements in, for example, B(---)s0→J/ψϕ decays. Assuming approximate SU(3) flavour symmetry and neglecting higher order diagrams, the shift in the CP-violating phase ϕs is limited to be within the interval [-1.05°, +1.18°] at 95% confidence level. Changes to the limit due to SU(3) symmetry breaking effects are also discussed.

Original languageEnglish (US)
Pages (from-to)38-49
Number of pages12
JournalPhysics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
StatePublished - 2015


ASJC Scopus subject areas

  • Nuclear and High Energy Physics

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