Measurement of the form factors for (B)over-bar(0)->D*(+)l(-)(nu)over-bar

Abstract

Using a sample of 2.6 x 10(6) Upsilon(4S) --> B (B) over bar events collected with the CLE (O) over right arrow II detector at the Cornell Electron Storage Ring, we have measured the form factors for (B) over bar(0) --> D*(+)l(-)<(nu)over bar>. We perform a three-parameter fit with the joint distribution of four kinematic variables to obtain the form-factor ratios R(1) = 1.18 +/- 0.30 +/- 0.12 and R(2) = 0.71 +/- 0.22 +/- 0.07, and the form-factor slope rho(A1)(2) = 0.91 +/- 0.15 +/- 0.06, which is closely related to the slope of the Isgur-Wise function. The form-factor ratios are consistent with predicted corrections to the heavy-quark symmetry limit R(1) = R(2) = 1.