title: Dynamical picture for the formation and decay of the exotic XYZ mesons.
abstract: We present a new dynamical picture that identifies the formation of the exotic c[over ¯]c-containing states XYZ with the confinement-induced hadronization of a rapidly separating pair of a compact diquark and antidiquark. This picture combines the advantages of diquark-based models, which can accommodate much of the known XYZ spectrum, with the experimental fact that such states are both relatively narrow and are produced promptly. It also naturally explains the preference of some of the exotic states to decay to ψ(2S), rather than J/ψ, in terms of a simple wave-function overlap effect.
authors.affiliation: SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94039, USA.
authors.forename: Stanley J
authors.initials: SJ
authors.lastname: Brodsky
authors.affiliation: Department of Physics, Sejong University, Seoul 143-747, South Korea.
authors.forename: Dae Sung
authors.initials: DS
authors.lastname: Hwang
authors.affiliation: Department of Physics, Arizona State University, Tempe, Arizona 85287-1504, USA.
authors.forename: Richard F
authors.initials: RF
authors.lastname: Lebed