Time evolution of the protostellar system: total mass of all the sink particles and the most massive sink particle are plotted as a function of time (top left). Total mass accretion rate by all sink particles are shown as a function of time (for others rotation parameter β₀; same as Fig. 3A). The cloud with zero rotation attains 30 M_⊙ within a few hundred years after the formation of the first sink particle. The rotationally supported cloud takes ~100−1000 yr, depending on the initial strength of rotation (β₀). The mass accretion rate decreases with time until further sink particles form.