Measurement of the CP-violating phase phi(s) in B-s(0) -> J/psi phi decays in ATLAS at 13 TeV

Creative Commons License

Aad G., Abbott B., Abbott D. C. , Abud A. A. , Abeling K., Abhayasinghe D. K. , ...More

EUROPEAN PHYSICAL JOURNAL C, vol.81, no.4, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 81 Issue: 4
  • Publication Date: 2021
  • Doi Number: 10.1140/epjc/s10052-021-09011-0


A measurement of the B-0(s) -> J/psi phi decay parameters using 80.5 fb(-1) of integrated luminosity collected with the ATLAS detector from 13 TeV proton-proton collisions at the LHC is presented. The measured parameters include the CP-violating phase phi(s), the width difference Delta Gamma(s) between the B-s(0) meson mass eigenstates and the average decay width Gamma(s). The values measured for the physical parameters are combined with those from 19.2 fb(-1) of 7 and 8 TeV data, leading to the following: phi(s) = -0.087 +/- 0.036 (stat.) +/- 0.021 (syst.) rad Delta Gamma(s) = 0.0657 +/- 0.0043 (stat.) +/- 0.0037 (syst.) ps(-1) Gamma(s) = 0.6703 +/- 0.0014 (stat.) +/- 0.0018 (syst.) ps(-1) Results for phi(s) and Delta Gamma(s) are also presented as 68% confidence level contours in the phi(s)-Delta Gamma(s) plane. Furthermore the transversity amplitudes and corresponding strong phases are measured. phi(s) and Delta Gamma(s) measurements are in agreement with the Standard Model predictions.