Amplitude analysis of the $\hat{I}{ž}_c^{+}\to p{K}^{-}\ddot{I}{€}^{+}$ decay and $\hat{I}{ž}_c^{+}$ baryon polarization measurement in semileptonic beauty-hadron decays

Abstract

An amplitude analysis of the $\hat{I}{ž}_c^{+}\to p{K}^{-}\ddot{I}{€}^{+}$ decay together with a measurement of the $\hat{I}{ž}_c^{+}$ polarization vector in semileptonic beauty-hadron decays is presented. The analysis is performed using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 ${\mathrm{fb}}^{-1}$. An amplitude model is developed and the resonance fractions as well as two- and three-body decay parameters are reported. A sizeable $\hat{I}{ž}_c^{+}$ polarization is found. A large sensitivity of the $\hat{I}{ž}_c^{+}\to p{K}^{-}\ddot{I}{€}^{+}$ decay to the polarization is seen, making the amplitude model suitable for $\hat{I}{ž}_c^{+}$ polarization measurements in other systems.

All figures and tables, along with any supplementary material and additional information, are available at https://lbfence.cern.ch/alcm/public/analysis/full-details/1602 (LHCb public pages)