Black Hole Formation Accompanied by the Supernova Explosion of a 40 M _⊙ Progenitor Star

Journal Article · 30 October 2023 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/acfc1c · OSTI ID:2204302

Burrows, Adam ; Vartanyan, David ; Wang, Tianshu

Abstract We have simulated the collapse and evolution of the core of a solar-metallicity 40 M _⊙ star and find that it explodes vigorously by the neutrino mechanism, despite its very high “compactness.” Within ∼1.5 s of explosion, a black hole forms. The explosion is very asymmetrical and has a total explosion energy of ∼1.6 × 10 ⁵¹ erg. At black hole formation, its baryon mass is ∼2.434 M _⊙ and gravitational mass is 2.286 M _⊙ . Seven seconds after black hole formation, an additional ∼0.2 M _⊙ is accreted, leaving a black hole baryon mass of ∼2.63 M _⊙ . A disk forms around the proto−neutron star, from which a pair of neutrino-driven jets emanates. These jets accelerate some of the matter up to speeds of ∼45,000 km s ⁻¹ and contain matter with entropies of ∼50. The large spatial asymmetry in the explosion results in a residual black hole recoil speed of ∼1000 km s ⁻¹ . This novel black hole formation channel now joins the other black hole formation channel between ∼12 and ∼15 M _⊙ discovered previously and implies that the black hole/neutron star birth ratio for solar-metallicity stars could be ∼20%. However, one channel leaves black holes in perhaps the ∼5–15 M _⊙ range with low kick speeds, while the other leaves black holes in perhaps the ∼2.5–3.0 M _⊙ mass range with high kick speeds. However, even ∼8.8 s after core bounce the newly formed black hole is still accreting at a rate of ∼2 × 10 ⁻² M _⊙ s ⁻¹ , and whether the black hole eventually achieves a significantly larger mass over time is yet to be determined.

• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0018297
• OSTI ID: 2204302
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 957; ISSN 0004-637X
• Publisher: American Astronomical SocietyCopyright Statement
• Country of Publication: United States
• Language: English