NONADIABATIC CONTRIBUTIONS TO STATIC 2-PION-EXCHANGE NUCLEAR-POTENTIALS

Recent evidence of the importance of the pion in the dynamics of few-n ucleon systems is reviewed. Calculations of the triton binding energy and the nucleon-nucleon phase shifts, and the application of chiral pe rturbation theory to few-nucleon systems, have highlighted the role of the pion. Qualitative aspects of chiral constraints in few-nucleon fo rces are reviewed, and the connection between the static Brueckner-Wat son and Taketani-Machida-Ohnuma two-pion-exchange two-nucleon forces i s shown to be the same as that between the Weinberg and Coon-Friar two -pion-exchange three-nucleon forces. Compact expressions for these for ces are given in the Appendix.