Study of the structure of e+e- -> b bbar g events and improved limits on the anomalous chromomagnetic coupling of the b-quark

Abstract

The structure of e+e- -> bbg events was studied using Z0 decays recorded in the SLD experiment at SLAC. Three-jet final states were selected and the CCD-based vertex detector was used to identify two of the jets as b or bbar. Distributions of the gluon energy and polar angle were measured over the full kinematic range, and compared with perturbative QCD predictions. The energy distribution is potentially sensitive to an anomalous b chromomagnetic moment kappa. We measured kappa to be consistent with zero and set limits on its value, -0.11 < kappa < 0.08 at 95% c.l. (preliminary).