The Interaction of Nucleons With Anti-nucleons. 2. Narrow Mesons Near Threshold: Experiment and Theory

Jan, 1979
87 pages
Published in:
  • Annals Phys. 121 (1979) 70
Report number:
  • BNL-24981

Citations per year

19791990200120122023024681012
Abstract: (Elsevier)
We compare and contrast several theoretical approaches which could account for a new class of narrow mesons recently observed in the mass region 1.5 – 3 GeV/c 2 , particularly those clustered near the antinucleon-nucleon ( N N ) threshold. We examine dual and quark models as well as N N potential models, focusing attention on differences between the quantum numbers of mesons predicted to lie near threshold. A preliminary comparison with data does not yet yield a strong preference for a particular model, although some crucial experiments are suggested. The main emphasis of this paper is on the meson spectrum predicted by N N potential models. In a previous work, referred to as I , we have discussed the level ordering of the spectrum for a number of realistic meson exchange models. In this sequel, we consider in more detail the candidates for narrow structures close to threshold. Estimates of the mixing of N N with other baryon-antibaryon configurations are given, as well as approximate values for the elastic and annihilation widths of these structures. We discuss criteria for identifying relatively pure N N states, as distinct from other multiquark complexes. We inquire to what extent useful constraints on the medium- and long-range nuclear forces could result from identification of an N N meson. Some speculations on the quantum numbers of the “new” mesons are presented.
  • HADRON SPECTROSCOPY: MESON
  • NUCLEON ANTINUCLEON: INTERACTION
  • INTERACTION: NUCLEON ANTINUCLEON
  • NUCLEON ANTINUCLEON: THRESHOLD
  • DUALITY
  • QUARK
  • NUCLEON ANTINUCLEON: POTENTIAL
  • INTERFERENCE: BARYON ANTIBARYON
  • QUANTUM NUMBER: MESON
  • BARYONIUM: DECAY WIDTH