000002531 001__ 2531
000002531 005__ 20210702030301.0
000002531 037__ $$aBELLE2-MTHESIS-2021-068
000002531 041__ $$aeng
000002531 100__ $$aYen-Ting Chin
000002531 245__ $$aSensitivity Study of $B^{+}\rightarrow \mu^{+}\nu$ in the Belle II Experiment
000002531 260__ $$aTaipei, Taiwan$$bNational Taiwan University$$c2021
000002531 300__ $$a89
000002531 500__ $$aPresented on 25 01 2021
000002531 502__ $$aMSc$$bTaipei, Taiwan, National Taiwan University$$c2021
000002531 520__ $$aIn this study, we intend to estimate the statistical significance of $B^{+}\rightarrow \mu^{+}\nu$ when various amounts of Belle II data are available in the future, assuming that the Standard Model estimation of the branching fraction of $B^{+}\rightarrow \mu^{+}\nu$ is correct. The Monte­ Carlo method is applied to generate a large amount of data samples to simulate the physics events produced by $e^{+}e^{-}$ collision on the center­-of­-mass energy of 10.58 GeV in the SuperKEKB accelerator. These physics events include the $e^{+}e^{-} \rightarrow q\bar{q}$, the $e^{+}e^{-} \rightarrow \tau^{+}\tau^{-}$ , and the $e^{+}e^{-} \rightarrow \Upsilon(4S) \rightarrow B^{0}\bar{B^{0}}/B^{+}B^{-}$ processes. The Belle II detector responses to these physics events are also simulated. In this study, we use multivariate analysis to distin­guish the $B^{+}\rightarrow \mu^{+}\nu$ events from the background events. We establish probability den­sity functions for different physics processes and generate Asimov data sets. We then use the profile likelihood function of the Asimov data sets to estimate the statistical signifi­cance of $B^{+}\rightarrow \mu^{+}\nu$ when different amounts of Belle II data are available. According to the estimation, we will need to collect more than 7 $ab^{-1}$ of data in order to surpass the significance of $5\sigma$ in order to claim the discovery of $B^{+}\rightarrow \mu^{+}\nu$.
000002531 700__ $$aPao-Ti Chang$$edir.
000002531 8560_ $$fandychin@hep1.phys.ntu.edu.tw
000002531 8564_ $$uhttps://docs.belle2.org/record/2531/files/BELLE2-MTHESIS-2021-068.pdf
000002531 980__ $$aTHESIS