Angular analysis of $B^0\to K^{\ast }(892{)}^0{\ell }^{+}{\ell }^{-}$

Abstract

We present a measurement of angular observables, $P_4^{\prime }$, $P_5^{\prime }$, $P_6^{\prime }$, $P_8^{\prime }$, in the decay $B^0\to K^{\ast }(892{)}^0{\ell }^{+}{\ell }^{-}$, where ${\ell }^{+}{\ell }^{-}$ is either $e^{+}{e}^{-}$ or $\hat{I}{¼}^{+}\hat{I}{¼}^{-}$. The analysis is performed on a data sample corresponding to an integrated luminosity of $711{\mathrm{fb}}^{-1}$ containing $772\times 10^6$ $B\bar{B}$ pairs, collected at the $\hat{I}\yen (4S)$ resonance with the Belle detector at the asymmetric-energy $e^{+}{e}^{-}$ collider KEKB. Four angular observables, $P_{4,5,6,8}^{\prime }$ are extracted in five bins of the invariant mass squared of the lepton system, $q^2$. We compare our results for $P_{4,5,6,8}^{\prime }$ with Standard Model predictions including the $q^2$ region in which the LHCb collaboration reported the so-called $P_5^{\prime }$ anomaly.

Conference paper for LHC Ski 2016. SM prediction for $P_6^{\prime }$ corrected and reference for arXiv:1207.2753 added