Search for B c + → π + μ + μ - decays and measurement of the branching fraction ratio B ( B c + → ψ ( 2 S ) π + ) / B ( B c + → J / ψ π + )

Journal article

The first search for nonresonant Bc+→π+μ+μ- decays is reported. The analysis uses proton–proton collision data collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9fb-1. No evidence for an excess of signal events over background is observed and an upper limit is set on the branching fraction ratio B(Bc+→π+μ+μ-)/B(Bc+→J/ψπ+)<2.1×10-4 at 90% confidence level. Additionally, an updated measurement of the ratio of the Bc+→ψ(2S)π+ and Bc+→J/ψπ+ branching fractions is reported. The ratio B(Bc+→ψ(2S)π+)/B(Bc+→J/ψπ+) is measured to be 0.254±0.018±0.003±0.005, where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the leptonic J/ψ and ψ(2S) decays. This measurement is the most precise to date and is consistent with previous LHCb results.

Authors: Aaij, R; Abdelmotteleb, A; Beteta, CA; Abudinén, F; Ackernley, T

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: SpringerOpen
• Journal: The European Physical Journal C
• Volume: 84
• Issue: 5
• Article number: 468
• Publication date: 2024-05-07
• Acceptance date: 2024-03-10
• DOI: 10.1140/epjc/s10052-024-12669-x
• EISSN: 1434-6052
• Language: English