Abstrakt
An absolute measurement of the A+c lifetime is reported using A+c -> pK-pi+ decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the (sic)(4S) resonance, is 207.2 fb(-1).
The result, tau(Lambda(+)(c)) = 203.20 10.89 10.77 fs, where the first uncertainty is statistical and the second systematic, is the most precise measurement to date and is consistent with previous determinations.