  The dynamical properties of partially coherent Bose-Einstein condensates in
double wells are investigated in three typical regimes. In the extreme Fock
regime, the time evolution of the degree of coherence is shown to decay
rapidly. In the Rabi regime, a relation between the amplitude of Rabi
oscillation and the degree of coherence is obtained, which is expected to
determine the degree of coherence by measuring the amplitude of Rabi
oscillation. The study on the self-trapping phenomena in the Josephson regime
exhibits that both the degree of coherence and the initial relative phase can
affect the final particle distribution.
