We report a measurement of CP-violating asymmetries in B° → (??)° →??−?° decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 375 million?(4S) → B{bar B} decays, collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure 26 coefficients of the bilinear form-factor terms occurring in the time-dependent decay rate of the B° meson. We derive the physically relevant quantities from these coefficients. In particular, we measure a constraint on the angle? of the Unitarity Triangle.

We report a measurement of CP-violating asymmetries in B{sup 0} {yields} ({rho}{pi}){sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 347 million {Upsilon}(4S) {yields} B{bar B} decays, collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure 26 coefficients of the bilinear form factor terms occurring in the time-dependent decay rate of the B{sup 0} meson and derive the physically relevant quantities from these coefficients. In particular we find a three standard deviation evidence of direct CP-violation in the B{sup 0} {yields} {rho}{sup {+-}}{pi}{sup {-+}} decays, with systematic uncertainties included. We also achieve a constraint of the angle {alpha} of the Unitarity Triangle. All results presented are preliminary.

We present results for a time-dependent Dalitz plot measurement of CP-violating asymmetries in the mode B^0 --> pi^+ pi^- pi^0, dominated by B^0 --> rho^\pm pi^\mp (rho^\pm --> pi^\pm pi^0) decays. Our dataset is derived from the complete sample of 471 x 10^6 B-Bbar meson pairs collected by the BABAR detector at the PEP-II asymmetric-energy e^+e^- collider at the SLAC National Accelerator Laboratory, operating on the Upsilon(4S) resonance. We extract parameters describing the time-dependent B^0 --> rho pi decay probabilities and CP asymmetries, including C, DeltaC, S, and DeltaS, finding these measurements to be consistent with the results of previous analyses. Additionally, we present a two-dimensional likelihood scan of the direct CP-violation asymmetry parameters for B^0 --> rho^\pm pi^\mp decays, finding the results to be consistent with direct CP violation at ~ 2 sigma significance. Finally, we present information on the CP-violating parameter alpha, corresponding to an angle in the unitarity triangle associated with the CKM quark-mixing matrix. We perform a likelihood scan of alpha that incorporates constraints from B^\pm --> rho pi measurements by means of isospin relationships. A robustness study assessing the reliability with which alpha is extracted provides important insights into the interpretation of this result.

We present a measurement of the time-dependent CP-violating asymmetries in B[sup 0] [yields] K*[sup 0][gamma](K*[sup 0] [yields] K[sub S][sup 0][pi][sup 0]) decays based on 124 million [Upsilon](4S) [yields] B[bar B] decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. In a sample containing 105 [+-] 14 signal decays, we measure S[sub K*[sub [gamma]]] = 0.25 [+-] 0.63 [+-] 0.14 and C[sub K*[sub [gamma]]] = -0.57 [+-] 0.32 [+-] 0.09, where the first error is 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.

The authors present a preliminary measurement of CP-violation parameters in the decay B° → KK−K{sub S}°, using approximately 465 million B{bar B} events collected by the BABAR detector at SLAC. Reconstructing the neutral kaon as K{sub S}° →?+?− or K{sub S}° →?°?°, they analyze the Dalitz plot distribution and measure fractions to intermediate states. They extract CP parameters from the asymmetries in amplitudes and phases between B° and {bar B}° decays across the Dalitz plot. From a fit to the whole Dalitz plot, they measure?{sub eff} = 0.44 ± 0.07 ± 0.02, A{sub CP} = 0.03 ± 0.07 ± 0.02, where the first uncertainties are statistical and the second ones are systematic. For decays to?K{sub S}°, they measure?{sub eff} = 0.13 ± 0.13 ± 0.02, A{sub CP} = 0.14 ± 0.19 ± 0.02. For decays to f0K{sub S}°, they measure?{sub eff} = 0.15 ± 0.13 ± 0.03, A{sub CP} = 0.01 ± 0.26 ± 0.07. From a fit to the region of the Dalitz plot with m{sub K{sup +}K−}> 1.1 GeV/c2, they measure?{sub eff} = 0.52 ± 0.08 ± 0.03, A{sub CP} = 0.05 ± 0.09 ± 0.04.