2003/05/02 by T. Barnes, F. E. Close, H. J. Lipkin · 1 citation
Physics and Astronomy · #hep-ph #nucl-th
paper · pdf · doi:10.1103/physrevd.68.054006
published as Phys.Rev.D68:054006,2003 · 6 pages, 1 figure
arxiv created 2003/05/02 · arxiv updated 2009/11/30
We discuss the implications of a possible quasinuclear DK bound state at 2.32 GeV. Evidence for such a state was recently reported in Ds+pio by the BaBar Collaboration. We first note that a conventional quark model c-sbar assignment is implausible, and then consider other options involving multiquark systems. An I=0 c sbar n nbar baryonium assignment is one possibility. We instead favor a DK meson molecule assignment, which can account for the mass and quantum numbers of this state. The higher-mass scalar c-sbar state expected at 2.48 GeV is predicted to have a very large DK coupling, which would encourage formation of an I=0 DK molecule. Isospin mixing is expected in hadron molecules, and a dominantly I=0 DK state with some I=1 admixture could explain both the narrow total width of the 2.32 GeV state as well as the observed decay to Ds+ pio. Additional measurements that can be used to test this and related scenarios are discussed.