Search for $CP$ violation and observation of $P$ violation in $\hat{I}{›}_b^0\to p\ddot{I}{€}^{-}\ddot{I}{€}^{+}\ddot{I}{€}^{-}$ decays

Abstract

A search for $CP$ violation in the $\hat{I}{›}_b^0\to p\ddot{I}{€}^{-}\ddot{I}{€}^{+}\ddot{I}{€}^{-}$ decay is performed using LHCb data corresponding to an integrated luminosity of 6.6$f{b}^{-1}$ collected in $pp$ collisions at centre-of-mass energies of 7, 8 and 13$TeV$. The analysis uses both triple product asymmetries and the unbinned energy test method. The highest significances of $CP$ asymmetry are 2.9 standard deviations from triple product asymmetries and 3.0 standard deviations for the energy test method. Once the global $p$-value is considered, all results are consistent with no $CP$ violation. Parity violation is observed at a significance of $5.5$ standard deviations for the triple product asymmetry method and $5.3$ standard deviations for the energy test method.

All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2019-028.html (LHCb public pages)