The D{sub J}{sup 0} is a family of four orbitally excited mesons: D*{sub 2}(2460){sup 0}, D{sub 1}(2420){sup 0}, D{sub 1}(j = 1/2){sup -}, and D*{sub 0}(j = 1/2){sup 0}. This dissertation presents the measurements of the inclusive branching fractions, {Beta}(B{sup -} {yields} D*{sup +}{pi}{sup -}{pi}{sup -}) and {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}). The D{sub J}{sup 0} provides an intermediate resonance for those two modes. The data used for this analysis consists of Runs 1-5 with total integrated luminosity of 343.38 fb{sup -1}, which is corresponding to 383.92 million B{bar B} pairs, provided by the BABAR detector at the PEP-II asymmetric B Factory. The values presented are: {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}) = (1.12 {+-} 0.02 {+-} 0.08) x 10{sup -3}; {Beta}(B{sup -} {yields} D*{sup +}{pi}{sup -}{pi}{sup -}) = (1.67 {+-} 0.03 {+-} 0.13) x 10{sup -3}.

In this work we presented measurements of CP violation and decay rates of B decays in final states not involving a charm quark in the final state. In particular, the time-dependent CP asymmetries of decays which proceed through b {yields} s elementary transition is a particularly sensitive probe of physics beyond the Standard Model. In fact, even if the precise measurements of CP conserving and CP violating processes show the success of the CKM picture of the flavour physics, the sector of b {yields} s transitions is still not strongly constrained and leaves room for new physics contributions. In particular, we considered the decays which have the cleanest theoretical prediction within the Standard Model: B{sup 0} {yields} {phi}K{sup 0} and B{sup 0} {yields} K{sub s}{sup 0}K{sub s}{sup 0}K{sub s}{sup 0} {beta}{sub eff}{sup SM} = 0.379. We examined the former with a completely new approach with respect to the past: the study of CP violation in the whole K{sup +}K{sup -}K{sup 0} phase space through a time-dependent Dalitz plot analysis. With this approach, we simultaneously measured the CP-violating asymmetries of the {phi}KJ{sup 0}, f{sub 0}(980)K{sup 0} resonant and K{sup +}K{sup -}K{sup 0} non-resonant contributions, avoiding one of the largest uncertainties which …

The rare decay B {yields} {pi}{ell}{sup +}{ell}{sup -} is the simplest manifestation of a b {yields} d{ell}{sup +}{ell}{sup -} flavor-changing neutral current (FCNC) process. This type of process only proceeds through penguin loop or box diagrams and is sensitive to physics at the electroweak scale. It can be used to constrain parameters of the Standard Model and its extensions. B {yields} {pi}{ell}{sup +}{ell}{sup -} events have not yet been observed; the branching fraction is expected to be an order of magnitude smaller than the measured branching fraction for the similar B {yields} K{ell}{sup +}{ell}{sup -} decay. Using 230 million B{bar B} meson pairs collected with the BABAR detector, we have done a search for the rare decay B {yields} {pi}{ell}{sup +}{ell}{sup -}. The data was produced in e+e? collision at the {Upsilon}(4S) resonance in the PEP-II collider between 1999 and 2004. Four exclusive B-meson decay modes have been reconstructed: B{sup +} {yields} {pi}{sup +}{ell}{sup +}{ell}{sup -} and B{sup 0} {yields} {pi}{sup 0}{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either an electron pair (e{sup +}e{sup -}) or a muon pair ({mu}{sup +}{mu}{sup -}). We find no evidence for a signal, and we obtain upper limits on the branching fractions {Beta}. …

None

This thesis reports measurements of the time-dependent CP asymmetries in fully reconstructed B{sup 0} {yields} (D{sup (*){-+}} and B{sup 0} {yields} D{sup {-+}} {rho}{sup {+-}}) decays in approximately 232 million {Upsilon}(4S) {yields} B{bar B} events, collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the Stanford Linear Accelerator Center in California, as published in Ref. [14]. The phenomenon of CP violation allows one to distinguish between matter and antimatter, and, as such, is one of the essential ingredients needed to explain the apparent abundance of matter over antimatter in the universe. The Standard Model describes the observed elementary particles in terms of three generations of quarks and leptons, as well as the weak, electromagnetic, and strong interactions between them. In the Standard Model, CP violation is incorporated in the Cabibbo-Kobayashi-Maskawa (CKM) matrix, which describes the weak interactions between the quarks. The weak interactions between quarks are described by coupling constants that are functions of three real parameters and one irreducible complex phase. The magnitude of all CP violating effects in the Standard Model is related to this complex phase. The measurement of the CP violating phase of the CKM matrix is an important part of the present …

The authors report the results of a study of the exclusive charmless semileptonic decay, B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, undertaken with approximately 227 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. They obtain partial branching fractions in 12 bins of q{sup 2}, the momentum transfer squared, from which they extract the f{sub +}(q{sup 2}) form-factor shape and the total branching fraction {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.46 {+-} 0.07{sub stat} {+-} 0.08{sub syst}) x 10{sup -4}. Based on a recent unquenched lattice QCD calculation of the form factor in the range q{sup 2} > 16 GeV{sup 2}/c{sup 4}, they find the magnitude of the CKM matrix element |V{sub ub}| to be (4.1 {+-} 0.2{sub stat} {+-} 0.2{sub syst{sub -0.4}{sup +0.6}FF}) x 10{sup -3}, where the last uncertainty is due to the normalization of the form factor.

None

Note that the main goal of this thesis work is the measurement of the branching fractions, charge asymmetry, and Time-Dependent CP Violation in {eta}'K{sup 0} mode. All other measurements are reported here for completion because they are connected by similar physics arguments. They are part of the Milan analysis activity, done by undergraduate students. They should not be considered as done in this thesis work. The measurements of the two body-modes {eta}{eta}, {eta}{phi}, and {eta}'{phi} are used to determine a theoretical bound based on SU(3) flavor symmetry for the difference between SM prediction and the experimental measurements of CP violation parameters in b {yields} s loop-dominated modes. In general for this estimation we need to measure the branching fractions (or upper limits) of neutral B decays to two-body modes with {eta}', {eta}, {phi}, {omega}, {pi}{sup 0}, K{sup 0}, K*{sup 0} [13, 14, 15, 16]. There is an important issue related to the branching fractions of {eta}'K (charged and neutral) modes. Since the discover of B {yields} {eta}'K in 1997 [17] with high branching fraction (higher than expected), it was found that the corresponding mode with {eta} is suppressed. This fact was pointed out by Lipkin in 1991 [18]. In particular, …

The objective of this work is to investigate the thick diffusion limit of various spatial discretizations of the one-dimensional, steady-state, monoenergetic, discrete ordinates neutron transport equation. This work specifically addresses the two lowest order nodal methods, AHOT-N0 and AHOT-N1, as well as reconsiders the asymptotic limit of the Diamond Difference method. The asymptotic analyses of the AHOT-N0 and AHOT-N1 nodal methods show that AHOT-N0 does not possess the thick diffusion limit for cell edge or cell average fluxes except under very limiting conditions, which is to be expected considering the AHOT-N0 method limits to the Step method in the thick diffusion limit. The AHOT-N1 method, which uses a linear in-cell representation of the flux, was shown to possess the thick diffusion limit for both cell average and cell edge fluxes. The thick diffusion limit of the DD method, including the boundary conditions, was derived entirely in terms of cell average scalar fluxes. It was shown that, for vacuum boundaries, only when {sigma}{sub t}, h, and Q are constant and {sigma}{sub a} = 0 is the asymptotic limit of the DD method close to the finite-differenced diffusion equation in the system interior, and that the boundary conditions between the systems will …

In the last two decades, the field of nanoscience andnanotechnology has witnessed tremendous advancement in the synthesis andapplication of group II-VI colloidal nanocrystals. The synthesis based onhigh temperature decomposition of organometallic precursors has becomeone of the most successful methods of making group II-VI colloidalnanocrystals. This method is first demonstrated by Bawendi and coworkersin 1993 to prepare cadmium chalcogenide colloidal quantum dots and laterextended by others to prepare other group II-VI quantum dots as well asanisotropic shaped colloidal nanocrystals, such as nanorod and tetrapod.This dissertation focuses on the chemistry of this type of nanocrystalsynthesis. The synthesis of group II-VI nanocrystals was studied bycharacterizing the molecular structures of the precursors and productsand following their time evolution in the synthesis. Based on theseresults, a mechanism was proposed to account for the 2 reaction betweenthe precursors that presumably produces monomer for the growth ofnanocrystals. Theoretical study based on density functional theorycalculations revealed the detailed free energy landscape of the precursordecomposition and monomerformation pathway. Based on the proposedreaction mechanism, a new synthetic method was designed that uses wateras a novel reagent to control the diameter and the aspect ratio of CdSeand CdS nanorods.

In the last two decades, the field of nanoscience andnanotechnology has witnessed tremendous advancement in the synthesis andapplication of group II-VI colloidal nanocrystals. The synthesis based onhigh temperature decomposition of organometallic precursors has becomeone of the most successful methods of making group II-VI colloidalnanocrystals. This methodis first demonstrated by Bawendi and coworkersin 1993 to prepare cadmium chalcogenide colloidal quantum dots and laterextended by others to prepare other group II-VI quantum dots as well asanisotropic shaped colloidal nanocrystals, such as nanorod and tetrapod.This dissertation focuses on the chemistry of this type of nanocrystalsynthesis. The synthesis of group II-VI nanocrystals was studied bycharacterizing the molecular structures of the precursors and productsand following their time evolution in the synthesis. Based on theseresults, a mechanism was proposed to account for the 2 reaction betweenthe precursors that presumably produces monomer for the growth ofnanocrystals. Theoretical study based on density functional theorycalculations revealed the detailed free energy landscape of the precursordecomposition and monomerformation pathway. Based on the proposedreaction mechanism, a new synthetic method was designed that uses wateras a novel reagent to control the diameter and the aspect ratio of CdSeand CdS nanorods.