Two-phase model of star formation with a variable rate of accretion

A two-phase model including the interaction between stars and molecular clouds is used to analyze the effect of accretion-rate variability on bursts of star formation (SF). SF is assumed to be induced by binary cloud collisions and the interaction between stars and already existing clouds. A damped-oscillation regime occurs in a variable-accretion system when the trigger mechanism of SF plays the dominant role. Three types of accretion variations are considered: a rapid increase during a time less than the oscillation period; a slow increase during two oscillation periods; and a short burst.