Exploring the threshold behavior and implications on the nature of Y(4260) and Zc(3900)

Abstract

We investigate several strong and radiative decay modes of Y(4260), by assuming that Y(4260) either is a D1D molecular state, or has sizeable couplings with D0D∗ and D′ 1D. In such ansatzes, obvious threshold enhancements or narrow cusp structures appear quite naturally without intro-ducing a genuine resonance. And we emphasize that the radiative decay modes may be useful for studying D(∗)D S-wave scattering.