  By building a general dynamical model for quantum measurement process,it is
shown that the factorization of reduced evolution operator sufficiently results
in the quantum mechanical realization of the wave packet collapse and the state
correlation between the measured system and the measuring
instrument-detector.This realizability is largely independent of the details of
both the interaction and Hamiltonian of detector. The Coleman-Hepp model and
all its generalizations are only the special cases of the more universal model
given in this letter.An explicit example of this model is finally given in
connection with coherent state.
