Year: 2026
Type: article
Abstract: We construct mass models of Milky Way dwarf spheroidal galaxies to place constraints on the central black hole masses they can host. We model the galaxies as a three-component system consisting of the stars, dark matter halo, and a central black hole, using the Osipkov–Merritt–Cuddeford class of the anisotropic distribution function. The posterior distribution of black hole mass remains flat toward the low-mass end, indicating that the kinematic data places an upper limit on the black hole mass. Our analysis yields a 95% credible upper limit of log ( M • / M ⊙ ) < 6 . We combine our results with black hole mass measurements and upper limits from the literature to construct a unified M • – σ * relation spanning σ * ∼ 10–300 km s −1 , described by log ( M • ) = 8.32 + 4.08 log σ * / 200 km s − 1 , with an intrinsic scatter of σ int = 0.55. We compare the inferred limits to models of black hole growth via momentum-driven accretion and stellar capture, which predict black hole masses in the range 10 3 –10 4 M ⊙ for the range σ * ∼ 6–12 km s −1 , in close agreement with the M • – σ * relation within the 95% credible upper limits on the black hole masses derived in this work.
Source: The Astrophysical Journal
Authors: K. Aditya, A. Mangalam
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Award: G6280841923
OpenAlex ID: W7125406018