A dynamical approach is developed to predict the scattering amplitudes starting with the constituent quark models. The first step is to apply a variational method to solve the three-quark bound state problem. The resulting wave functions are used to calculate the vertex functions by assuming that the and mesons couple directly to quarks. These vertex functions and the predicted baryon bare masses then define a Hamiltonian for reactions. We apply a unitary transformation method to derive from the constructed Hamiltonian a multichannel and multiresonance reaction model for predicting the scattering amplitudes up to GeV. With the parameters constrained by the excitation, we have examined the extent to which the scattering in the channel can be described by constituent quark models based on one-gluon-exchange or one-meson exchange mechanisms. It is found that the data seem to favor the spin-spin interaction due to one-meson exchange and the tensor interaction due to one-gluon exchange. A phenomenological quark-quark potential has been constructed to reproduce the amplitude.
- Received 16 August 1999
- Revised 3 February 2000
- Published 17 May 2000
© 2000 The American Physical Society