Many-Quark Model with su(4) Algebraic Structure
  With the use of a certain type of the Schwinger boson representation of the su(4) algebra, the Bonn model for many-quark systems and an extension of the model, in which the energies of the various exact states are controled, namely, the energies are enhanced or de-enhanced, are investigated. Especially, the triplet formation and the pairing correlation in many-quark states are discussed. In the boson space, all the results are analytically expressed in the exact forms. 
Y. Tsue (Kochi Univ., Japan), C. Providencia (Univ. de Coimbra,   Portugal), J. da Providencia (Univ. de Coimbra, Portugal),...