\(\etap K\) puzzle of B meson decays and new physics effects in the TC2 model

Abstract

Using the low energy effective Hamiltonian with the generalized factorization, we calculate the new physics contributions to \(B \to \pi^+ \pi^-, K \pi\) and \(K \etap\) in the Topcolor-assisted-Technicolor(TC2) model, and compare the results with the available data. By using \(F_0^{{\rm B\pi}}(0)=0.20\pm 0.04\) preferred by the CLEO data of \(B \to \pi^+ \pi^-\) decay, we find that the new physics enhancements to \(B \to K \etap\) decays are significant in size, \(\sim 50%\) with respect to the standard model predictions, insensitive to the variations of input parameters and hence provide a simple and plausible new physics interpretation for the observed unexpectedly large \(B\to K \etap\) decay rates.