The CP violating phase β^J/ψφ_s is measured in decays of B⁰_s → J/ψφ. This measurement uses 5.2 fb^-1 of data collected in √s = 1.96 TeV p‾p collisions at the Fermilab Tevatron with the CDF Run-II detector. CP violation in the B⁰_s-‾B⁰_sbar system is predicted to be very small in the Standard Model. However, several theories beyond the Standard Model allow enhancements to this quantity by heavier, New Physics particles entering second order weak mixing box diagrams. Previous measurements have hinted at a deviation from the Standard Model expectation value for β^J/ψφ_s with a significance of approximately 2σ. The measurement described in this thesis uses the highest statistics sample available to date in the B⁰_s → J/ψφ decay channel, where J/ψ → μ⁺ μ^- and φ → K⁺K^-. Furthermore, it contains several improvements over previous analyses, such as enhanced signal selection, fully calibrated particle ID and flavour tagging, and the inclusion of an additional decay component in the likelihood function. The added decay component considers S-wave states of KK pairs in the B⁰_s → J/ψK⁺K^- channel. The results are presented as 2-dimensional frequentist confidence regions for β^J/ψφ<sub >s</sub> and ΔΓ (the width difference between the B⁰_s mass eigenstates), and as a confidence interval for β^J/ψφ_s of [0.02,0.52] U [1.08, 1.55] at the 68% confidence level. The measurement of the CP violating phase obtained in this thesis is complemented by the world's most precise measurement of the lifetime τ_s = 1.53 ± 0.025 (stat.) ± 0.012 (syst.) ps and decay width difference ΔΓ = 0.075 ± 0 .035 (stat.) ± 0.01 (syst.) ps⁻¹ of the B⁰_s meson, with the assumption of no CP violation.

This thesis presents two studies of charged charm meson decays using proton- proton collision data, corresponding to an integrated luminosity of 3 fb⁻¹, recorded by the LHCb experiment. A search for D_(s)^&plus; &rarr; &pi;^&plus;&mu;^&plus;&mu;^- decays is performed. Rare decays of charged charm mesons have not previously been observed unlike their counterpart B meson and kaon decays. Such decays are c &rarr; u quark transitions and take place via loop diagrams within the Standard Model. Measurements of their branching fractions are an indirect test of New Physics, whose virtual contributions may enhance such quantities. No signals are observed and the 90&percnt; (95&percnt;) CL limits on the branching fractions, the most stringent to date, are found to be, B(D^&plus; &rarr; &pi;^&plus;&mu;^&plus;&mu;^-) &LT; 2.9 (3.3) × 10^-8, B(D_s^&plus; &rarr; &pi;^&plus;&mu;^&plus;&mu;^-) &LT; 1.76 (1.91) × 10^-7. The charge asymmetry measurement of D+ &rarr; &pi;+&pi;0 using &pi;0 &rarr; e^&plus;e^-&gamma; decays is also described. Charge asymmetry in the Standard Model is expected to be small for charm meson decays. Any measured deviation from zero would be evidence of New Physics. This decay has not previously been observed at a hadron collider and the measurement acts as a 'proof of principle' study allowing a future analysis to examine the decay mode. No evidence of CP violation is found.

Using data equivalent to an integrated luminosity of 3 fb⁻¹ collected by the LHCb experiment during Run I (2011-2012), studies of beauty mesons decaying to a final state containing open charm are performed, concluding with a number of new results. Direct CP-violation is explored in <i>B</i>^± → <i>Dh</i>^± decays through several measurements of CP violating observables, where the charmed meson <i>D</i> is reconstructed in both 2-track and 4-track final states. A measurement of the <i>B</i>^± production asymmetry at LHCb is reported using <i>B</i>^± → <i>D</i>π^± decays, and a complementary measurement of the CP asymmetry in <i>B</i>^± → <i>J</i>/ψ<i>K</i>^± decays made. A search for the rare <i>B</i>_c− → <i>D</i>(*)π⁻ and B_c− → <i>D</i> (*)<i>K</i>⁻ decays concludes this work.

This thesis documents searches for direct CP violation in the Cabibbo-suppressed D+ to K-K+pi+ decay at the LHCb experiment. Two complementary analyses are described. Direct CP-violating asymmetries are predicted to exist in singly Cabibbo-suppressed charm decays with magnitudes of up to O(0.001) in the Standard Model, and can be enhanced to the percent level by contributions from new physics. No such asymmetry has yet been observed. The LHCb detector is a forward spectrometer with a precise vertex detector and powerful particle identification capabilities, designed to collect large, pure samples of charm and $B$ decays. Data collected at LHCb in 2010 corresponding to an integrated luminosity of 35pb^-1 are used to perform a model-independent search for direct CP violation in the D+ to K-K+pi+ decay. The Dalitz plot is divided into bins and a chi^2 test of the compatibility of the dataset with no CP violation is performed. No evidence of CP violation is found. A second search for CP violation in the region of the D+ to K-K+pi+ Dalitz plot around the phi resonance is described. The charge asymmetry in this decay is calculated and compared to that in the control channel D+ to Ks(pi+pi-)pi+. The 1.0fb^-1 of data collected at LHCb in 2011 are used. The CP-violating asymmetry is found to be (-0.04+/-0.14+/-0.14)% where the uncertainties are statistical and systematic, respectively. A new observable sensitive to CP violation that varies across the phi resonance is defined and measured, and is consistent with no CP violation at the current level of sensitivity. In addition, the CP-violating asymmetry in the decay Ds+ to Ks pi+ is determined to be (0.61+/-0.83+/-0.14)%. There is no evidence for CP violation in either channel. The prospects for new results using data collected in 2012 are very promising and a significant improvement in our understanding of these decays is anticipated.

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No description available.

This thesis describes two pieces of work. The first is a study of the resolution of the LHCb vertex locator throughout Run 1. The second comprises analyses to measure the charm mixing and CP violation observables A_{Gamma} and y_{CP}.An estimate of the resolution of the LHCb vertex locator is required for use in the track fits. A method to measure the resolution with collision data has been developed and tested. The performance of the sub-detector throughout Run 1 of the LHC has been assessed. A significant degrading of the resolution has been seen. The effects of this on the track reconstruction has been examined with little change in the measured quantities being observed. The measurement of indirect CP violation in neutral D meson transitions has been measured through the observables A_{Gamma} and y_{CP}, using 1fb^{-1} of pp collisions with a centre of mass energy 7TeV, collected by the LHCb detector in 2011.A_{Gamma} describes the CP asymmetry of the lifetime of the D^0 decaying to a CP eigenstate (KK or pipi). The analysis documented here yields A_{Gamma} = (-0.17+-0.54)x10^{-3} when the measurements are combined. This is the world's best measurement and represented a factor of four improvement over the previous best result. The observable y_{CP} compares the effective lifetimes of the Cabibbo favoured decay D^0→Kpi and the transition to a CP eigenstate (KK or pipi). The unblinded result obtained in this document, averaged over both final states is y_{CP} = (5.61+-1.56)x10^{-3}. This result is commensurate with the world average central value within 1.25 standard deviations and has significance of 3.6 standard deviations relative to zero.

No description available.

A search for B decays to quasi two-body charmless final states involving a pseudoscalar η′ meson recoiling against a K∗ vector meson is described. This thesis primarily describes the analysis of two of the six possible decay channels, with the other four channels necessarily included as the subdecay modes are combined to give an overall branching fraction measurement. The method of analysis is a multivariate maximum likelihood fit for each subdecay channel. The likelihood curves for both modes are then combined, firstly with two other charged modes to yield an overall charged result, and finally the four charged modes are combined with two neutral modes to give an overall branching fraction and significance for the decay channel B → η′K∗. All results use the full Run 1 to Run 4 datasets, comprising 210.5 fb−1 of data, equivalent to 232 million BB pairs, gathered by the BABAR detector at Stanford Linear Accelerator Center in Menlo Park, California. The measured branching fractions and upper limits at 90% confidence limit (CL) are: B(B+ → η′ηππK∗+ K+π0) < 9.5 × 10−6B(B+ → η′ργK∗+ K+π0) < 22 × 10−6.The four-mode combined fit determined the branching fraction for the decay B+ → η′K∗+: B(B+ → η′K∗+) < 7.9 × 10−6. The six-mode combined fit determined the branching fraction for the decay B → η′K∗: B(B → η′K∗) = (4.1 ± 1.0 ± 0.5) × 10−6 at a significance of 5.6 standard deviations.

It is astonishing both how little and how much we know about neutrinos. On one hand, the neutrino is the second most abundant particle in our Universe. Neutrinos may be created in the Sun, core collapse supernovae, cosmic rays, geological background radiation, supernova remnants and in the Big Bang. On the other hand, they have unimaginably small masses and are unwilling to react with their surroundings. Because of their abundance and their inclination to show us physics beyond the standard model of particle physics, neutrinos are hoped to carry yet unknown information of the Universe. However, it will take some effort and time to persuade the neutrinos to tell us what they know. Among the things we do not yet know of the neutrinos, is the -phase in the neutrino mixing matrix. If is in fact non-zero, neutrino flavour oscillations violate CP-symmetry. Also, if neutrino masses are introduced in the standard model through the See-Saw mechanism and if leptogenesis is a valid theory, CP-violation in neutrino oscillations could help explain why our Universe has no antimatter even though equal amounts of matter and antimatter should have been created at the Big Bang. In this thesis, we investigate the flavour evolution of supernova neutrinos. We present the full Hamiltonian in the flavour basis for our system and identify how the different contributions affect the evolution and in which environment. We also present a theoretical motivation from [1, 2] as to how a non-zero -phase affects the flavour evolution and the final energy spectra. The analytical conclusion is that it has no impact under the assumptions made in our analysis. Thus, the -phase may not be measurable from supernova neutrinos.