Search for the decay $B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-}$ at the Belle experiment

Abstract

This letter presents a search for the rare flavor-changing neutral current process $B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-}$ using data taken with the Belle detector at the KEKB asymmetric energy $e^{+}{e}^{-}$ collider. The analysis is based on the entire ${\rm Y}(4S)$ resonance data sample of 711 $\mathrm{f}{\mathrm{b}}^{-1}$, corresponding to $772\times 10^{6}B\bar{B}$ pairs. In our search we fully reconstruct the companion $B$ meson produced in the process $e^{+}{e}^{-}\to {\rm Y}(4S)\to B\bar{B}$ from its hadronic decay modes, and look for the decay $B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-}$ in the rest of the event. No evidence for a signal is found. We report an upper limit on the branching fraction $\mathcal{B}(B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-})<3.1\times 10^{-3}$ at 90\% confidence level. This is the first direct limit on $\mathcal{B}(B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-})$.

8 pages, 3 figures, accepted by PRD as a Letter

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Cited by in corpus (8)

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• Flavor physics in SU(5) GUT with scalar fields in the 45 representation
• Exploring New Physics in transition $b\to s{\ell }^{+}{\ell }^{-}$ through different $B_c\to D_s^{(\ast )}{\ell }^{+}{\ell }^{-}$ observables
• Scrutinizing $B^0$-meson flavor changing neutral current decay into scalar $K_0^{\ast }(1430)$ meson with $b\to s{\ell }^{+}{\ell }^{-}(\nu \bar{\nu })$ transition
• Search for $B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-}$ decays at the Belle II experiment
• Design, performance and future prospects of vertex detectors at the FCC-ee
• Searches for $B^0\to K^{+}{\pi }^{-}{\tau }^{+}{\tau }^{-}$ and $B_s^0\to K^{+}{K}^{-}{\tau }^{+}{\tau }^{-}$ decays
• Search for the decay $B^{+}\to K^{+}{\tau }^{+}{\tau }^{-}$ using data from the Belle and Belle II experiments