Revisiting nonfactorizable contributions to factorization-forbidden decays of $B$ mesons to charmonium

Abstract

Motivated by the observed large rates of B → (χc0, χc2, hc)K decays by BABAR and Belle collaborations, we investigate the nonfactorizable contributions to these factorization-forbidden decays, which can occur via a gluon exchange between the cc system and the spectator quark. Our numerical results demonstrate that the spectator contributions are able to produce a large branching ratio consistent with experiments. As a by-product, we also study the Cabibbo-suppressed decays, such as B → (χc0, χc2, hc)π and the U-spin related Bs decay, which receive less attention from both theory and experiment. The calculated branching ratios reach the order of 10 −6 , which are in the scope of Belle-II and LHCb experiments. Besides, the CP -asymmetry parameters are also calculated for these decays. The obtained results are compared with available experimental data and numbers from other predictions. We also investigate the sources of theoretical uncertainties in our calculation.

Implications for new physics from a novel puzzle in $\bar{B}_{(s)}^0 \to D^{(\ast)+}_{(s)} \lbrace π^-, K^- \rbrace$ decays

“…Eventually, we obtain Since g 22 = g 11 is a necessary condition, this model also produces new physics contributions to b → ccs processes with the same size [52,53]. Alhough they, e.g., B + → J/ψK + , have been measured precisely, the SM predictions suffer from large nonfactorizable corrections [54][55][56]. We, therefore, expect that the b → ccs processes are less sensitive than b → cūq.…”