Looking for meson molecules in B decays

Abstract

We discuss the possibility of observing a loosely bound molecular state in a B three-body hadronic decay. In particular we use the QCD sum rule approach to study a $\eta^\prime-\pi$ molecular current. We consider an isovector-scalar $I^G J^{PC}= 1^-~0^{++}$ molecular current and we use the two-point and three-point functions to study the mass and decay width of such state. We consider the contributions of condensates up to dimension six and we work at leading order in $\alpha_s$. We obtain a mass around 1.1 GeV, consistent with a loosely bound state, and a $\eta^\prime-\pi\rightarrow K^+ K^-$ decay width around 10 MeV.