New measurement of BR(D+→ρ0μ+ν)BR(D+→K¯∗0μ+ν) branching ratio

Abstract Using data collected by the FOCUS experiment at Fermilab, we present a new measurement of the charm semileptonic branching ratio BR ( D + → ρ 0 μ + ν ) BR ( D + → K ¯ ∗ 0 μ + ν ) . From a sample of 320 ± 44 and 11372 ± 161 D + → ρ 0 μ + ν and D + → K − π + μ + ν events respectively, we find BR ( D + → ρ 0 μ + ν ) BR ( D + → K ¯ ∗ 0 μ + ν ) = 0.041 ± 0.006 ( stat ) ± 0.004 ( syst ) .