Measurements of the CP content and CP violating asymmetries in neutral B decays to two Dmesons with the BABAR detector

This dissertation presents a measurement of time-dependent CP -violating asymmetries and a measurement of the CP-odd parity fraction in the decay B0 → D*+D*-. The measurements are derived from a data sample of 88 x 106 BB¯ pairs collected by the BABAR detector at the PEP-II asymmetric-energy B Factory located at the Stanford Linear Accelerator Center. A one-dimensional angular analysis of the decay products measures the CP-odd fraction to be 0.063 +/- 0.055(stat) +/- 0.009(syst), indicating that the D* +D*- final state is mostly CP-even. The time-dependent CP asymmetry parameters Iml+ and | l+ | are determined from an analysis of the time-dependence of flavor-tagged B decays. One neutral B meson is fully reconstructed in a D*+D* - final state, while the other B is inclusively reconstructed in order to determine its flavor. The Standard Model predicts the CP asymmetry parameters Iml+ and | l+ | to be -sin2beta and 1, respectively, in the absence of penguin diagram contributions. They are determined to be 0.05 +/- 0.29(stat) +/- 0.10(syst) and 0.75 +/- 0.19(stat) +/- 0.02(syst), respectively, which corresponds to a 2.5 sigma deviation from Standard Model predictions with penguin contributions ignored.