Precision measurement of the D?0 decay branching fractions

Abstract

Using 482 pb-1 of data taken at s=4.009 GeV, we measure the branching fractions of the decays of D?0 into D0?0 and D0? to be B(D?0?D0?0)=(65.5±0.8±0.5)% and B(D?0?D0?)=(34.5±0.8±0.5)%, respectively, by assuming that the D?0 decays only into these two modes. The ratio of the two branching fractions is B(D?0?D0?0)/B(D?0?D0?)=1.90±0.07±0.05, which is independent of the assumption made above. The first uncertainties are statistical and the second ones systematic. The precision is improved by a factor of 3 compared to the present world average values. © 2015 American Physical Society.