Direct measurements of absolute branching fractions for D0D0 and D+D+ inclusive semimuonic decays

By analyzing approximately 33 pb−1 of sample data collected at and around 3.773 GeV with the BES-II detector at the BEPC collider, we directly measured the branching fractions for the neutral and charged D   inclusive semimuonic decays to be BF(D0→μ+X)=(6.8±1.5±0.8)%BF(D0→μ+X)=(6.8±1.5±0.8)% and BF(D+→μ+X)=(17.6±2.7±1.8)%BF(D+→μ+X)=(17.6±2.7±1.8)%, and determined the ratio of the two branching fractions to be BF(D+→μ+X)BF(D0→μ+X)=2.59±0.70±0.25.