Abstract
Recent experimental results on nucleon-antinucleon annihilation reactions of the type N¯N→πX have provided evidence for a new mesonic state with quantum numbers ()=() which lies outside of the usual quark-antiquark (QQ¯) tensor meson nonet of flavor SU(3). We show that the observed production rates of from atomic p¯p states of orbital angular momentum L=0,1, as well as the decay characteristics of , namely, its preference for ρρ over ππ decay and the absence of an observable K¯K mode, are consistent with an interpretation of as a quasinuclear bound state of the N¯N potential. The principal binding mechanism for such states is provided by the coherent tensor forces for isospin I=0 which arise from meson exchanges. We review the evidence for the () and () states predicted in this model and apply the strong-coupling quark model to estimate the decay branching ratios for a variety of N¯N bound states. Key experimental tests of our interpretation are discussed.
- Received 18 July 1990
DOI:https://doi.org/10.1103/PhysRevC.43.379
©1991 American Physical Society