Second Quantization for an Absorptive System of Many Composite Particles: With Application to Nuclear Reaction Theory

Abstract

A new Hamiltonian is proposed as a convenient basis for discussing a many composite-particle system in which nuclear reactions take place. Feshbach's projection operators are generalized so as to apply to the many-particle system, and the concept of Dyson's ideal spin-wave states is extended to bound states of many nucleons. The Hamiltonian thus constructed is expressed in terms of nuclear creation and annihilation operators which obey the simple commutation rules. It is shown that, when the present formalism is applied to nuclear reaction theory, the transition amplitude describes in a unified way both the direct and resonant processes, as in Feshbach's unified reaction theory.