Measurement of the lifetime of the doubly charmed baryon $\hat{I}{ž}_{cc}^{++}$

Abstract

The first measurement of the lifetime of the doubly charmed baryon $\hat{I}{ž}_{cc}^{++}$ is presented, with the signal reconstructed in the final state $\hat{I}{›}_c^{+}{K}^{-}\ddot{I}{€}^{+}\ddot{I}{€}^{+}$. The data sample used corresponds to an integrated luminosity of $1.7{\mathrm{fb}}^{-1}$, collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of $13\mathrm{Te}\mathrm{V}$. The $\hat{I}{ž}_{cc}^{++}$ lifetime is measured to be $0.256{}_{-0.022}^{+0.024}(\mathrm{stat})\pm 0.014(\mathrm{syst})\mathrm{ps}$.

All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2018-019.html