000001064 001__ 1064
000001064 005__ 20180731200355.0
000001064 037__ $$aBELLE2-CONF-PROC-2018-013
000001064 041__ $$aeng
000001064 100__ $$aJo-Frederik Krohn
000001064 245__ $$aSemileptonic B-Meson decays at Belle II
000001064 260__ $$a$$c2018-07-31
000001064 300__ $$a6
000001064 520__ $$aThe Belle II experiment is the upgrade of the Belle experiment, performed at the SuperKEKB asymmetric electron-positron-collider, located in Tsukuba, Japan. With an design instantaneous luminosity of $8\cdot 10^{35}\rm{cm}^{-2}\rm{s}^{-1}$ a dataset of $50\ \rm{ab}^{-1}$ will be collected. The clean collision environment of the experiment and the large dataset yields the ability to perform high precision measurements of physics mediated by the weak force, such as semileptonic $B$-meson decays. Of special focus of this document are magnitudes of the CKM matrix elements $\rm{V_{\rm{ub}}}$ and $\rm{V_{\rm{cb}}}$ measured in $B\to D^{(\star)} l \nu$ and $B\to \pi l \nu$, where $l = e,\mu$, as well as the ratio of the branching fractions, $R_{D^{(\star)}} := \mathcal{B} (B\to D^{(\star)} e \nu) / \mathcal{B} (B\to D^{(\star)} \mu \nu)  $ and $R_{\tau} :=  \mathcal{B} (B\to D^{(\star)} \tau\nu) / \mathcal{B} (B\to D^{(\star)} l \nu) $ , of lepton couplings in these decays. Some of these have shown persistent tension with the Standard Model and are therefore of primary interest towards a better understanding of the weak force carriers and potential new physics couplings.
000001064 8560_ $$fjo-frederik.krohn@desy.de
000001064 8564_ $$uhttps://docs.belle2.org/record/1064/files/BELLE2-CONF-PROC-2018-013.pdf