2012/02/29 by LHCb Collaboration, C. Abellán Beteta, R. Aaij +603
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevlett.108.241801
published as Phys. Rev. Lett. 108, 241801 (2012) · 7 pages, 4 figures, published on Physical Review Letters
openalex publication_date 2012/06/11 · arxiv created 2012/07/19 · arxiv updated 2012/07/20 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
The interference between the K+K^\ensuremath- S-wave and P-wave amplitudes in Bs0\ensuremath→J/\ensuremathψK+K^\ensuremath- decays with the K+K^\ensuremath- pairs in the region around the \ensuremathφ(1020) resonance is used to determine the variation of the difference of the strong phase between these amplitudes as a function of K+K^\ensuremath- invariant mass. Combined with the results from our CP asymmetry measurement in Bs0\ensuremath→J/\ensuremathψ\ensuremathφ decays, we conclude that the Bs0 mass eigenstate that is almost CP=+1 is lighter and decays faster than the mass eigenstate that is almost CP=\ensuremath-1. This determines the sign of the decay width difference \ensuremathΔ\ensuremathΓs\ensuremath≡\ensuremathΓL\ensuremath-\ensuremathΓH to be positive. Our result also resolves the ambiguity in the past measurements of the CP violating phase \ensuremathφs to be close to zero rather than \ensuremathπ. These conclusions are in agreement with the standard model expectations.