Nadia Toutounji ; Kevin Varvell

2019
The University of Sydney Sydney

Abstract: The Belle II detector located in Tsukuba, Japan, building on the work of its predecessor Belle, is scheduled for long-term data collection from electron-positron $e^{+} e^{-}$ collisions commencing in early 2019, for the purpose of studying rare B-meson decays in the search for new physics beyond the Standard Model. The Belle II Analysis Software Framework (BASF2) has been developed for physics analyses, with the Full Event Interpretation (FEI) being one such method designed for the reconstruction of B-meson decays from detector information. The FEI must be trained on simulated Monte Carlo (MC) data and introduces a signal-specific training process that can be tailored for a particular decay of interest in an attempt to increase the performance over signal-independent training processes such as those employed in Full Reconstruction (FR) methods at Belle. This study investigates the performance of the signal-specific and signal-independent FEI algorithms in the context of rare semi-leptonic B-meson decays, in comparison to leptonic decays, with the respective modes $B^{+} \to \rho^{0} \mu^{+} \nu_{\mu}$ and $B^{+} \to \tau^{+} \nu_{\tau}$ chosen as working examples. The relative performance of the FEI methods implemented is evaluated via a number of key performance indicators including the reconstruction efficiency and purity of the reconstructed $\Upsilon(4S)$ event.

Note: Presented on 21 01 2019
Note: MSc