Measurement of the D0 and $D^+$ Lifetimes

We have used a high-resolution drift chamber in the Mark II detector at the SLAC e+e- storage ring PEP to measure the lifetimes of the D0 and D+ mesons produced in e+e- annihilations at 29 GeV. Based on a sample of 74 decays for the D0 mesons and 23 decays for the D+ mesons, the lifetimes are found to be &=(4.7-0.8+0.9) 0.5×10-13 sec and &=(8.9-2.7+3.8) 1.3×10-13 sec. This leads to a ratio of lifetimes &=1.9-0.7 0.3+0.9.. AE © 1986 The American Physical Society.