Distribution of delay times for SD (solid line) and DD models (DDC, long dashed; DDW; short dashed) used in this paper. Because of the choice of parameters (see text) the DDC DTD accommodates a large fraction of prompt events, while the DDW DTD is relatively flat. The dash-dotted line is a a power law . All DTDs considered are equal to zero at delay times shorter than 40 Myr (the evolutionary lifetime of a ≃8 M_⊙ star), and are normalized to 1 in the range 40 Myr ≤ t_D ≤ 13 Gyr.