The quantum numbers of the X(3872) meson are determined to be JPC=1 ++ based on angular correlations in B +→X(3872)K + decays, where X(3872)→π +π -J/ψ and J/ψ→μ +μ -. The data correspond to 1.0 fb -1 of pp collisions collected by the LHCb detector. The only alternative assignment allowed by previous measurements JPC=2 - + is rejected with a confidence level equivalent to more than 8 Gaussian standard deviations using a likelihood-ratio test in the full angular phase space. This result favors exotic explanations of the X(3872) state.
All Science Journal Classification (ASJC) codes
- Física y astronomía (todo)