Postponed bifurcations of a ring-laser model with a swept parameter and additive colored noise

We present measurements of the time evolution of the statistical densities of both amplitude and field intensity obtained from a colored-noise-driven electronic circuit model of a ring laser, as the bifurcation parameter is swept through its critical values. The time-dependent second moments (intensities) were obtained from the densities. In addition, the individual stochastic trajectories were available from which the distribution of bifurcation times was constructed. For short-correlation-time (quasiwhite) noise our results are in quantitative agreement with the recent calculations of Boggi, Colombo, Lugiato, and Mandel [Phys. Rev. A 33, 3635 (1986)]. New results for long noise correlation times are obtained.