2005/01/12 by Abaz Kryemadhi, Kryemadhi, Abaz
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #hep-ex
paper · pdf · doi:10.48550/arxiv.hep-ex/0501029
166 pages, PhD Thesis
arxiv created 2005/01/20 · arxiv updated 2009/12/01
We have performed a search for CPT violation in neutral charm meson oscillations using data from the FOCUS Experiment. While flavor mixing in the charm sector is predicted to be small by the Standard Model, it is still possible to investigate CPT violation through a study of the proper time dependence of a CPT asymmetry in right-sign decay rates for D0→ K-π+ and \d0b→ K+π-. This asymmetry is related to the CPT violating complex parameter ξ and the mixing parameters x and y: ACPT∝\rm Re ξy-\rm Im ξx. Our 95% confidence level limit is -0.0068<\rm Re ξy-\rm Im ξx<0.0234. Within the framework of the Standard Model Extension incorporating general CPT violation, we also find 95% confidence level limits for the expressions involving coefficients of Lorentz violation. We present measurements of the \lb lifetime in the exclusive decay channel \lbdec with J/ψ→ μ+ μ- and Λ→ p π-, the B0 lifetime in the decay \bddecks with J/ψ→ mu+ μ- and K0S → π+ π-, and the ratio of these lifetimes. The analysis is based on approximately 225 pb-1 of data recorded with the DØdetector in p barp collisions at √(s) =1.96 TeV. The \lb lifetime is determined to be τ(Λ0b) = 1.36 ± 0.3 ps, the B0 lifetime τ(Λ0b) = 1.43 ± 0.12 ps, and the ratio \fr acτ(Λb)τ(Bd)=0.95±0.22. In contrast with previous measurements using semileptonic decays, this is the first determination of the \lb lifetime based on a fully reconstructed decay channel.