EFFECTIVE-FIELD THEORY FOR LOW-ENERGY 2-NUCLEON SYSTEMS

We illustrate how effective field theories work in nuclear physics by using an effective Lagrangian in which all other degrees of freedom th an the nucleonic one have been integrated out to calculate the low-ene rgy properties of two-nucleon systems, viz., the deuteron properties, the np S-1(0) scattering amplitude, and the M1 transition amplitude en tering into the radiative np capture process. Exploiting a finite cuto ff regularization procedure, we find all the two-nucleon low-energy pr operties to be accurately described with little cutoff dependence, in consistency with the general philosophy of effective field theories.