Decay of b-Flavored Hadrons to Single-Muon and Dimuon Final States

An enhancement in the inclusive cross section for single muons produced in e/sup +/e/sup -/ annihilations at the UPSILON(4S) is observed, confirming the interpretation that a new bare flavor (B mesons) is produced at the UPSILON(4S). A branching ratio for B..-->..X..mu nu.. of (9.4 +- 3.6)% is obtained. The two-muon decay, B..-->..X..mu../sup +/..mu../sup -/, is not observed, providing a 90%-confidence-level upper limit for the branching ratio for the decay of 1.7%. Combining this with our previously reported limit of 5% for B..-->..Xe/sup +/e/sup -/, we obtain 1.3% as an upper limit for B..-->..Xl/sup + -/.