First observation of the decays B-0 -> D*- p(p)over-tilde pi(+) and B-0 -> D*- p(n)over-bar

Abstract

We report the first observation of exclusive decays of the type B --> D*N (N) over barX, where N is a nucleon. Using a sample of 9.7 X 10(6)B (B) over bar pairs collected with the CLEO detector operating at the Cornell Electron Storage Ring, we measure the branching fractions B(B-0 --> D*(-) p (p) over bar pi (+)) = (6.5(-1.2)(+1.3) +/- 1.0) X 10(-4) and B(B-0 --> D*(-) p (n) over bar) = (14.5(-3.0)(+3.4) +/- 2.7) X 10(-4). Antineutrons are identified by their annihilation in the CsI electromagnetic calorimeter.