Measurement of the ${\Omega }_c^0$ baryon lifetime

Abstract

We report a measurement of the lifetime of the ${\Omega }_c^0$ baryon using proton-proton collision data at center-of-mass energies of 7 and 8~TeV, corresponding to an integrated luminosity of 3.0 fb${}^{-1}$ collected by the LHCb experiment. The sample consists of about 1000 ${\Omega }_b^{-}\to {\Omega }_c^0{\mu }^{-}{\bar{\nu }}_{\mu }X$ signal decays, where the ${\Omega }_c^0$ baryon is detected in the $p{K}^{-}{K}^{-}{\pi }^{+}$ final state and $X$ represents possible additional undetected particles in the decay. The ${\Omega }_c^0$ lifetime is measured to be ${\tau }_{{\Omega }_c^0}=268\pm 24\pm 10\pm 2$ fs, where the uncertainties are statistical, systematic, and from the uncertainty in the $D^{+}$ lifetime, respectively. This value is nearly four times larger than, and inconsistent with, the current world-average value.

7 pages, 2 figures. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2018-028.html