Search for $B^+\to K^{*+}\tau^\pm \ell^\mp$ with hadronic tagging at the Belle II experiment

Several observables in the flavor sector, including the charged current ratio \(\mathcal{R}(D^{(*)})\) and the evidence for neutral current \(B^+\to K^+\nu\bar\nu\) have been hinting at deviation from the Standard Model.
Many proposed extensions predict enhanced rates for lepton flavor violating transitions such as \(b \to s \tau\ell\), as there is no fundamental symmetry protecting lepton flavor conservation. 

This thesis provides first estimates of the upper limits on the branching fractions for \(B^+\to K^{*+}\tau^\pm \ell^\mp\) decay modes, using simulated samples corresponding to a dataset of \(365\,\mathrm{fb}^{-1}\) collected at the\(\Upsilon (4\mathrm{S})\) resonance by the Belle II experiment. The accompanying \(B\) meson is reconstructed exclusively via hadronic decay modes, enabling signal extraction via a fit to the reconstructed invariant mass of the \(\tau\) lepton.