Poles and Poltergeists in e^+ e^- → D D̅ Data

A recent report of e^+ e^- → DD̅ events by the BESIII Collaboration suggests the presence of a structure R at 3900 MeV. We argue that this structure, called G(3900) in the past, is not in fact due to a new cc̅ resonance, but rather naturally emerges as a threshold enhancement due to the opening of the D^*D̅ channel. We further find that the appearance of this structure does not require suppression because of a radial node in the ψ(4040) wave function, although a node improves fit quality. The measured e^+ e^- coupling of ψ(4040) is found to be substantially smaller than previously estimated. In addition, we report new corrections to the measured cross section σ(e^+ e^- → DD̅) at energies near ψ(3770).