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Abstract

To date, modern three-dimensional (3D) supernova (SN) simulations have not demonstrated that explosion energies of 10⁵¹ erg (=1 bethe=1 B) or more are possible for neutrino-driven SNe of non/slow-rotating M < 20 M_⊙ progenitors. We present the first such model, considering a nonrotating, solar-metallicity 18.88 M_⊙ progenitor, whose final 7 minutes of convective oxygen-shell burning were simulated in 3D and showed a violent oxygen–neon shell merger prior to collapse. A large set of 3D SN models was computed with the PROMETHEUS-VERTEX code, whose improved convergence of the two-moment equations with Boltzmann closure allows now to fully exploit the implicit neutrino-transport treatment. Nuclear burning is treated with a 23-species network. We vary the angular grid resolution and consider different nuclear equations of state and muon formation in the proto-neutron star (PNS), which requires six-species transport with coupling of all neutrino flavors across all energy–momentum groups. Elaborate neutrino transport was applied until ∼2 s after bounce. In one case, the simulation was continued to >7 s with an approximate treatment of neutrino effects that allows for seamless continuation without transients. A spherically symmetric neutrino-driven wind does not develop. Instead, accretion downflows to the PNS and outflows of neutrino-heated matter establish a monotonic rise of the explosion energy until ∼7 s post-bounce, when the outgoing shock reaches ∼50,000 km and enters the He layer. The converged value of the explosion energy at infinity (with overburden subtracted) is ∼1 B and the ejected ⁵⁶Ni mass ≲0.087 M_⊙, both within a few 10% of the SN 1987A values. The final NS mass and kick are ∼1.65 M_⊙ and >450 km s⁻¹, respectively.