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arXiv · 2210.07779

Robust Supermassive Black Hole Spin Mass-Energy Characteristics: A New Method and Results

Abstract

The rotational properties of astrophysical black holes are fundamental quantities that characterization the black holes. A new method to empirically determine the spin mass-energy characteristics of astrophysical black holes is presented and applied here. Results are obtained for a sample of 100 supermassive black holes with collimated dual outflows and redshifts between about zero and two. An analysis indicates that about two-thirds of the black holes are maximally spinning, while one-third have a broad distribution of spin values; it is shown that the same distributions describe the quantity $\rm{(M_{rot}/M_{irr})}$. The new method is applied to obtain the black hole spin mass-energy, $\rm{M_{spin}}$, available for extraction relative to: the maximum possible value, the irreducible black hole mass, and the total black hole mass, $\rm{M_{dyn}}$. The total energy removed from the black hole system and deposited into the circumgalactic medium via dual outflows over the entire outflow lifetime of the source, $\rm{E_T}$, is studied relative to $\rm{M_{dyn}}$ and relative to the spin energy available per black hole, $\rm{E_{spin}/(M_{\odot}c^2)}$. The mean value of $\rm{Log(E_T/M_{dyn})}$ is about $(-2.47\pm 0.27)$. Several explanations of this and related results are discussed. For example, the energy input to the ambient gas from the outflow could turn off the accretion, or the impact of the black hole mass loss on the system could destabilize and terminate the outflow. The small values and restricted range of values of $\rm{Log(E_T/M_{dyn})}$ and $\rm{Log(E_T/E_{spin})}$ could suggest that these are fundamental properties of the primary process responsible for producing the dual collimated outflows.

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BibTeXRIS

Ruth A. Daly. 2022-10-14. Robust Supermassive Black Hole Spin Mass-Energy Characteristics: A New Method and Results. https://doi.org/10.1093/mnras%2Fstac2976

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