THE EFFECT OF ETA-ETA' MIXING IN THE BOUND STATE VERSION OF THE SKYRME MODEL

摘要

The eta-eta' mixing is incorporated in the symmetry breaking term in the extended Skyrme model Lagrangian. Besides eta-soliton bound states, an s-wave and a p-wave eta'-soliton bound states are found. After fixing the value of the strength parameter X of the ''alternative term'' to fit the s-wave eta'-soliton bound state to the N(1535) negative-parity nucleon resonance, the eta-soliton bound states disappear. Then only eta'-soliton bound states are identified with nucleon resonances (I = 1/2) and delta resonances (I = 3/2). The predicted resonance masses agree well experimental values. The decay widths Gamma(N*-->N+eta) of the relevant nucleon resonances are also calculated to explain why these particles have large branching ratios in the eta N channel. [References: 21]