Effects of enhancedZpenguin diagrams on lepton polarizations inB→Xsℓ+ℓ−

Abstract

The sensitivity of the $B\ensuremath{\rightarrow}\ensuremath{\pi}K$ mode to electroweak penguin diagrams and the recent experimental data for the $B\ensuremath{\rightarrow}\ensuremath{\pi}\ensuremath{\pi},\ensuremath{\pi}K$ modes has given rise to what is known as the ``$B\ensuremath{\rightarrow}\ensuremath{\pi}K$ puzzle.'' Recently it has been observed that this puzzle can be resolved by considering the new physics which can enter via ${Z}^{0}$ penguin diagrams. In this note we analyze the effect of these enhanced ${Z}^{0}$ penguin diagrams on the lepton polarization asymmetries of $b\ensuremath{\rightarrow}s{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$.