This thesis presents an analysis of the CP-violating asymmetry in B0--B0bar meson mixing, utilising the Run 2 dataset collected by the LHCb experiment. The decay channel B0->D-mu+neu, followed by D-->K+pi-pi-, is employed. A two-dimensional fit of the corrected B meson mass and B meson decay time is performed on non-D background-subtracted samples to simultaneously extract the CP asymmetry a_sl^d and the B0--B0bar production asymmetry A_P. Detection asymmetries, comprising a combination of kaon-pion detection asymmetry and muon-pion detection asymmetry, are estimated using independent calibration samples and incorporated into the measurement. The primary systematic uncertainties arise from the muon PID and trigger asymmetry and kaon-pion detection asymmetry. The blinded results are as follows: a_sl^d = 0.0077+-0.0009(stat)+-0.0016(syst), A_P = -0.0056+-0.0005(stat)+-0.0008(syst). Additionally, this thesis explores the potential for integrating Opticks, a GPU-accelerated optical photon simulation package, with the LHCb detector simulation framework to enhance efficiency and performance. The hybrid workflow, which combines Geant4 and Opticks, delegates CPU optical photon simulation to GPUs, thereby improving the overall simulation speed. The consistency of results obtained from Geant4 and Opticks simulations is corroborated using a simplified RICH 1 geometry, demonstrating the viability of the proposed methodology. The ongoing transition to the NVIDIA OptiX 7 API and the re-architecture of Opticks GPU code are expected to further augment the package's capabilities.
CP violation in neutral B meson oscillations and fast optical photon simulation on GPUs
Li, Y. (Author). 31 Dec 2023
Student thesis: Phd