Abstract
Collapsing stars constitute the main black hole (BH) formation channel, and are occasionally associated with the launch of relativistic jets that power γ-ray bursts (GRBs). Thus, collapsars offer an opportunity to infer the natal (before spin-up/down by accretion) BH spin directly from observations. We show that once the BH saturates with a large-scale magnetic flux, the jet power is dictated by the BH spin and mass accretion rate. Core-collapse simulations by Halevi et al. and GRB observations favor stellar density profiles that yield an accretion rate of m ̇ ≈ 10 − 2 M ⊙ s − 1 , weakly dependent on time. This leaves the spin as the main factor that governs the jet power. By comparing the jet power to characteristic GRB luminosities, we find that the majority of BHs associated with jets are likely born slowly spinning with a dimensionless spin of a ≃ 0.2, or a ≃ 0.5 for wobbling jets, with the main uncertainty originating in the unknown γ-ray radiative efficiency. This result could be applied to the entire core-collapse BH population, unless an anticorrelation between the stellar magnetic field and angular momentum is present. In a companion paper, Jacquemin-Ide et al., we show that regardless of the natal spin, the extraction of BH rotational energy leads to spin-down to a ≲ 0.2, consistent with gravitational-wave observations. We verify our results by performing the first 3D general-relativistic magnetohydrodynamic simulations of collapsar jets with characteristic GRB energies, powered by slowly spinning BHs. We find that jets of typical GRB power struggle to escape from the star, providing the first numerical indication that many jets fail to generate a GRB.
| Original language | English (US) |
|---|---|
| Article number | L32 |
| Journal | Astrophysical Journal Letters |
| Volume | 952 |
| Issue number | 2 |
| DOIs | |
| State | Published - Aug 1 2023 |
Funding
We thank the referee for helpful comments. O.G. is supported by a CIERA Postdoctoral Fellowship. O.G. and A.T. acknowledge support by Fermi Cycle 14 Guest Investigator program 80NSSC22K0031. J.J. and A.T. acknowledge support by the NSF AST-2009884 and NASA 80NSSC21K1746 grants. B.L. acknowledges support by a National Science Foundation Graduate Research Fellowship under grant No. DGE-2234667. B.L. also acknowledges support by a Illinois Space Grant Consortium (ISGC) Graduate Fellowship supported by a National Aeronautics and Space Administration (NASA) grant awarded to the ISGC. A.T. was also supported by NSF grants AST-2107839, AST-1815304, AST-1911080, AST-2206471, and OAC-2031997, and NASA grant 80NSSC18K0565. Support for this work was also provided by the National Aeronautics and Space Administration through Chandra Award Number TM1-22005X issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. This research used resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC05-00OR22725. An award of computer time was provided by the ASCR Leadership Computing Challenge (ALCC), Innovative and Novel Computational Impact on Theory and Experiment (INCITE), and OLCF Director’s Discretionary Allocation programs under award PHY129. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 using NERSC award ALCC-ERCAP0022634. We thank the referee for helpful comments. O.G. is supported by a CIERA Postdoctoral Fellowship. O.G. and A.T. acknowledge support by Fermi Cycle 14 Guest Investigator program 80NSSC22K0031. J.J. and A.T. acknowledge support by the NSF AST-2009884 and NASA 80NSSC21K1746 grants. B.L. acknowledges support by a National Science Foundation Graduate Research Fellowship under grant No. DGE-2234667. B.L. also acknowledges support by a Illinois Space Grant Consortium (ISGC) Graduate Fellowship supported by a National Aeronautics and Space Administration (NASA) grant awarded to the ISGC. A.T. was also supported by NSF grants AST-2107839, AST-1815304, AST-1911080, AST-2206471, and OAC-2031997, and NASA grant 80NSSC18K0565. Support for this work was also provided by the National Aeronautics and Space Administration through Chandra Award Number TM1-22005X issued by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics Space Administration under contract NAS8-03060. This research used resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC05-00OR22725. An award of computer time was provided by the ASCR Leadership Computing Challenge (ALCC), Innovative and Novel Computational Impact on Theory and Experiment (INCITE), and OLCF Director’s Discretionary Allocation programs under award PHY129. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 using NERSC award ALCC-ERCAP0022634.
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science