Measurement of the relative B- →d0 /D∗0 /D∗∗0μ- ν μ branching fractions using B- mesons from B s2∗0 decays

The decay of the narrow resonance (B) over bar (s2)*(0) -> B(-)K(+)can be used to determine the B- momentum in partially reconstructed decays without any assumptions on the decay products of the r meson. This technique is employed for the first time to distinguish contributions from D-0, D*(0), and higher-mass charmed states (D**(0)) in semileptonic B- decays by using the missing-mass distribution. The measurement is performed using a data sample corresponding to an integrated luminosity of 3.0 fb(-1) collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV. The resulting branching fractions relative to the inclusive B- -> (DX)-X-0 mu(-)(nu) over bar (mu) are f(D)(0)= B(B- -> D-0 mu(-)(nu) over bar mu/B(B- -> (DX)-X-0 mu(-)(nu) over bar (mu)) = 0.25 +/- 0.06, f (D)**(0) = B(B- -> (D**(0) -> (DX)-X-0)mu(-)(nu) over bar (mu))/B(B--> (DX)-X-0 mu(-)(nu) over bar (mu)) = 0.21 +/- 0.07, with f(D)*(0) = 1 - f(D)(0) - f(D)**(0) making up the remainder.