摘要
We present self-consistent, 3D core-collapse supernova simulations of a 40 Msun progenitor model using the isotropic diffusion source approximation for neutrino transport and an effective general relativistic potential up to∼0.9 s postbounce. We consider three different rotational speeds with initial angular velocities ofΩ₀=0 , 0.5, and 1 rad s ⁻¹and investigate the impact of rotation on shock dynamics, black hole formation, and gravitational wave signals. The rapidly-rotating model undergoes an early explosion at∼ 250 ms postbounce and shows signs of the lowT/|W|instability. We do not find black hole formation in this model within∼ 460 ms postbounce. In contrast, we find black hole formation at 776 ms postbounce and 936 ms postbounce for the non-rotating and slowly-rotating models, respectively. The slowly-rotating model explodes at∼ 650 ms postbounce, and the subsequent fallback accretion onto the proto-neutron star (PNS) results in BH formation. In addition, the standing accretion shock instability induces rotation of the proto-neutron star in the model that started with a non-rotating progenitor. Assuming conservation of specific angular momentum during black hole formation, this corresponds to a black hole spin parameter ofa=J/M=0.046 . However, if no explosion sets in, all the angular momentum will eventually be accreted by the BH, resulting in a non-spinning BH. The successful explosion of the slowly-rotating model drastically slows down the accretion onto the PNS, allowing continued cooling and contraction that results in an extremely high gravitational-wave frequency ( f∼3000 Hz) at black hole formation, while the non-rotating model generates gravitational wave signals similar to our corresponding 2D simulations.