SURVIVAL PROBABILITY FOR THE YAMAGUCHI POTENTIAL

Different decay behaviours of the survival probability are examined. T echnically, the survival probability of an arbitrary state psi is dete rmined by the psi matrix element of the resolvent of the full Hamilton ian. The analytical properties of this matrix element can be analyzed in terms of the properties of the kernel of the Lippmann-Schwinger equ ation. For the Yamaguchi potential and several initial states, all fun ctions are explicitly calculated. This approach allows the decompositi on of the survival amplitude into a sum of decaying exponential terms and w-functions associated with the pole positions of the resolvent ma trix element in the complex momentum plane. Novel decay behaviours are found for the decay of states associated with the resolvent poles and the decay of a state which is dominated by the form of the wave funct ion rather than by the resolvent poles. Certain anomalous short time d ecay behaviour is also exemplified. (C) 1996 Academic Press, Inc.