Implications of family nonuniversalZ′model onB→K0*(1430)πdecays

Abstract

Within the QCD factorization formalism, we study the possible impacts of the nonuniversal ${Z}^{\ensuremath{'}}$ model, which provides a flavor-changing neutral current at the tree level, on rare decays $B\ensuremath{\rightarrow}{K}_{0}^{*}(1430)\ensuremath{\pi}$. Under two different scenarios, Scenerio-1 (S1) and Scenerio-2 (S2), for identifying the scalar meson ${K}_{0}^{*}(1430)$, the branching ratios, $CP$ asymmetries, and isospin asymmetries are calculated in both the standard model and the family nonuniversal ${Z}^{\ensuremath{'}}$ model. We find that the branching ratios and $CP$ asymmetries are sensitive to weak annihilation. In the standard model, with ${\ensuremath{\rho}}_{A}=1$ and ${\ensuremath{\phi}}_{A}\ensuremath{\in}[\ensuremath{-}30\ifmmode^\circ\else\textdegree\fi{},30\ifmmode^\circ\else\textdegree\fi{}]$, the branching ratios of S1 (S2) are smaller (larger) than the experimental data. Adding the contribution of the ${Z}^{\ensuremath{'}}$ boson in two different cases (Case I and Case II), for S1, the branching ratios are still far away from experiment. For S2, in Case II, the branching ratios become smaller and can accommodate the data; in Case I, although the center values are enhanced, they can also explain the data with large uncertainties. Similar conclusions are also reached for $CP$ asymmetries. Our results indicate that S2 is more favored than S1, even after considering new physics effects. Moreover, if there exists a nonuniversal ${Z}^{\ensuremath{'}}$ boson, Case II is preferred. All results can be tested in the LHC-b experiment and forthcoming super-$B$ factory.