Noise-induced phase transitions in globally coupled active rotators

We study the nonequilibrium phenomena in a globally coupled active rotator model with multiplicative noise. It is shown that at the critical values of the noise intensity the system undergoes noise-induced phase transitions and forms clusters. From the Fokker-Planck equation, which describes dynamics of the system, we analytically obtain the critical noise intensity at specific values of the parameter space. Numerical simulations reveal the phase transitions producing peculiar phase diagrams. The nature of the transitions is also discussed in detail.