2021-11-2922:14 The Belle II vertex detector alignment studies and prompt $\sin{2\phi_1}$ analysis / Jakub Kandra ; prof. RNDr. Zdenek Dolezal, Dr. [BELLE2-PTHESIS-2021-019] Presented on 26 11 2021 PhD 2021 Institute of Particle and Nuclear Physics / Prague This thesis is focused on the alignment studies of the vertex detector during first years of the Belle II detector operation and the first prompt $\sin{2\phi_1}$ analysis using the first relevant data collected by the detector. [...] Fulltext: PDF; 2021-11-2817:09 First application of CsI(Tl) pulse shape discrimination at an $e^+ e^-$ collider to improve particle identification at the Belle II experiment / Savino Longo ; John Michael Roney [BELLE2-PTHESIS-2021-018] Presented on 07 10 2019 PhD 2019 University of Victoria / Victoria This dissertation investigates CsI(Tl) pulse shape discrimination (PSD) as a novel experimental technique to improve challenging areas of particle identification at high energy $e^+ e^-$ colliders using CsI(Tl) calorimeters. [...] Fulltext: PDF; 2021-11-1808:55 Performance study of the SVD detector of Belle II and future upgrades / Ludovico Massaccesi ; Francesco Forti [BELLE2-MTHESIS-2021-078] Presented on 25 10 2021 MSc 2021 Università di Pisa / Pisa SuperKEKB is a B factory: an asymmetric e+e- collider designed to operate at a centre-of-mass energy of 10.58 GeV, corresponding to the peak of the Y(4S) vector meson resonance, which decays to a BBbar pair over 96% of the times. [...] Fulltext: PDF; 2021-10-1407:17 Characterization of the Particle Identification of the Belle II Detector with Bhabha Radiation and First Measurement of sin(2φ1) and ∆md Using Belle II Data / Justin Skorupa ; Allen Caldwell ; Frank Simon ; Hans-Günther Moser ; et al [BELLE2-MTHESIS-2021-077] Presented on 29 03 2021 MSc 2021 Max Planck Institut für Physik / München Characterization of the Particle Identification of the Belle II Detector with Bhabha Radiation and First Measurement of sin(2φ1) and ∆md Using Belle II Data Fulltext: PDF; 2021-10-0712:46 Background Analysis for $B^0$ Lifetime and Oscillation Frequency Measurement using Hadronic $B^0\rightarrow D^{(*)-}\pi^+$ Channels at Belle II / Caspar Schmitt ; Christian Kiesling ; Thibaud Humair [BELLE2-MTHESIS-2021-076] Presented on 13 09 2021 MSc 2021 Max-Planck Institute for Physics / Munich To explain the origin of the observed matter-antimatter asymmetry in the universe, new sources of charge-parity (CP) symmetry violation beyond the standard model of particle physics are required. [...] Fulltext: PDF; 2021-10-0403:20 Search for D+ → K- K0s π+ π+ π0 at the Belle Experiment and Development of the Read-Out System for the Pixel Detector of the Belle II Experiment / Dmytro Levit ; Stephan Paul [BELLE2-PTHESIS-2021-017] Presented on 13 02 2019 PhD 2019 Technische Universität München / München The thesis describes development of a read-out system of the pixel detector at Belle II and search for a rare D+decay in full data sample of Belle experiment. [...] Fulltext: PDF; 2021-09-0213:30 Tagged Analysis of $B^0\to\pi^-\ell^+\nu_\ell$ at Belle / Jonathan Wolfgang Grumke ; Jochen Dingfelder ; Peter Lewis [BELLE2-MTHESIS-2021-075] Presented on 25 08 2021 MSc 2021 Physikalisches Institut / Bonn Using the FEI algorithm with simulated data for hadronic tagging in the reconstruction of $B^0\to\pi^-\ell^+\nu_\ell$ results in a signal yield of $626\pm 39$ when applying the same selections as Sibidanov et al., who used the FR algorithm and obtained a signal yield of $463\pm 28$. [...] Fulltext: PDF; 2021-09-0213:19 Investigation of B → µ ν_µ with Inclusive Tagging at Belle II / Daniel Jacobi ; Prof. Dr. Jochen Dingfelder ; Dr. Peter Lewis ; Svenja Katharina Granderath [BELLE2-MTHESIS-2021-074] Presented on 25 08 2021 MSc 2021 Physikalisches Institut / Bonn In this thesis the rare $B \to \mu \nu_{\mu}$ decay was investigated using the inclusive tagging approach. [...] Fulltext: PDF; 2021-09-0207:05 First Conceptual Design and Studies for a Tracking Time Projection Chamber for the Belle II Experiment / Andreas Löschcke Centeno ; Jochen Dingfelder ; Peter Lewis [BELLE2-MTHESIS-2021-073] Presented on 30 08 2021 MSc 2021 Physikalisches Institut / Bonn This thesis deals with simulating a tracking time projection chamber (TPC) for the \Btwo experiment at the SuperKEKB accelerator and using the simulation for first studies. [...] Fulltext: PDF; 2021-08-2016:01 Searches for an invisible Z' and for the dark Higgsstrahlung A'h' process in μ⁺μ⁻ plus missing energy final states at Belle II / Marcello Campajola ; Guglielmo De Nardo ; Francesco Di Capua [BELLE2-PTHESIS-2021-016] Presented on 24 06 2021 PhD 2021 Università di Napoli "Federico II" / Napoli (IT) The work presented in this thesis concerns two searches for dark sector mediators in \emep\ annihilations at the center-of-mass energy of 10.58~GeV with the Belle II experiment [...]