The authors present updated measurements of time-dependent Cp asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 ± 5) x 106 [Upsilon](4S) 2!B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric energy ee− storage rings operating at the SLAC National Accelerator Laboratory. The time-dependent CP asymmetry parameters measured from J/[psi] K{sub S}°, J/[psi]K{sub L}°, [psi](2S)K{sub S}°, [eta]{sub c}K{sub S}°, [chi]{sub c1}K{sub S}° and J/[psi] K*(892)° decays are: C{sub f} = 0.024 ± 0.020(stat) ± 0.016(syst) and -[eta]{sub f}S{sub f} = 0.687 ± 0.028(stat) ± 0.012(syst).

We present results on time-dependent CP asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 227 x 106 [Upsilon](4S) → B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The amplitude of the CP asymmetry, sin2[beta] in the Standard Model, is derived from decay-time distributions from events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B° or {bar B}° from its decay products. We measure sin2[beta] = 0.722 ± 0.040(stat) ± 0.023(syst) in agreement with the Standard Model expectation.

The authors present an updated measurement of the time-dependent CP-violating asymmetry in B{sup 0} {yields} K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0} decays based on 347 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. The authors obtain the CP asymmetries S{sub f} = -0.66 {+-} 0.26 {+-} 0.08 and C{sub f} = -0.14 {+-} 0.22 {+-} 0.05, where the first uncertainties are statistical and the second systematic.

This thesis describes a high-quality, high-precision method for the data analysis of an interesting elementary particle reaction. The data was collected at the Japanese B-meson factory KEKB with the Belle detector, one of the most successful large-scale experiments worldwide. CP violation is a subtle quantum effect that makes the world look different when simultaneously left and right and matter and antimatter are exchanged. This being a prerequisite for our own world to have developed from the big bang, there are only a few experimental indications of such effects, and their detection requires very intricate techniques. The discovery of CP violation in B meson decays garnered Kobayashi and Maskawa, who had predicted these findings as early as 1973, the 2008 Nobel prize in physics. This thesis describes in great detail what are by far the best measurements of branching ratios and CP violation parameters in two special reactions with two charm mesons in the final state. It presents an in-depth but accessible overview of the theory, phenomenology, experimental setup, data collection, Monte Carlo simulations, (blind) statistical data analysis, and systematic uncertainty studies.

We present updated measurements of time-dependent CP asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 ± 5) x 106 [Upsilon](4S) → B{bar B} decays collected with the BABAR detector at the PEP-II B factory. The time-dependent CP asymmetry parameters measured from J/[psi]K{sub S}°, J/[psi]K{sub L}°, [psi](2S)K{sub S}°, [chi]{sub c1}K{sub S}°, [eta]{sub c}K{sub S}°, and J/[psi]K*° decays are: (1) C{sub f} = 0.026 ± 0.020(stat) ± 0.016(syst); and (2) S{sub f} = 0.691 ± 0.029(stat) ± 0.014(syst).

We present new measurements of time-dependent CP asymmetries for B° --> D{sup (*)+}d{sup (*)-} decays using (467 ± 5) x 106 B{bar B} pairs collected with the BABAR detector located at the PEP-II B Factory at the Stanford Linear Accelerator Center. We determine the CP-odd fraction of the B° --> D*D*− decays to be R(up tack) = 0.158 ± 0.028 ± 0.006 and find CP asymmetry parameters for the CP-even component of the decay S+ = -0.76 ± 0.16 ± 0.04 and C+ = 0.00 ± 0.12 ± 0.02. We measure S = -0.63±0.36±0.05 and C = -0.07±0.23±0.03 for B° --> DD−, S = -0.62±0.21±0.03 and C = 0.08 ± 0.17 ± 0.04 for B° --> D*+D−, and S = -0.73 ± 0.23 ± 0.05 and C = 0.00 ± 0.17 ± 0.03 for B° --> D+D*−. For the B° --> D*{sup ±}D{sup {-+}} decays, we also determine the CP-violating asymmetry A = 0.008 ± 0.048 {+-} 0.013. In each case, the first uncertainty is statistical and the second is systematic. The measured values for the asymmetries are all consistent with the Standard Model.