Black Hole Scaling Relations in the Dwarf-galaxy Regime with $Gaia$-Sausage/Enceladus and $\omega$Centauri

Abstract

The discovery of fast moving stars in the Milky Way's most massive globular cluster, $\omega$Centauri ($\omega$Cen), has provided strong evidence for an intermediate-mass black hole (IMBH) inside of it. However, $\omega$Cen is known to be the stripped nuclear star cluster (NSC) of an ancient, now-destroyed, dwarf galaxy. The best candidate to be the original host progenitor of $\omega$Cen is the tidally disrupted dwarf $Gaia$-Sausage/Enceladus (GSE), a former Milky Way satellite as massive as the Large Magellanic Cloud. I compare $\omega$Cen/GSE with other central BH hosts and place it within the broader context of BH-galaxy (co)evolution. The IMBH of $\omega$Cen/GSE follows the scaling relation between central BH mass and host stellar mass (${\mathrm{M}}_{\mathrm{BH}}-{\mathrm{M}}_{\star }$) extrapolated from local massive galaxies (${\mathrm{M}}_{\star }\gtrsim 10^{10}{\mathrm{M}}_{\odot }$). Therefore, the IMBH of $\omega$Cen/GSE suggests that this relation extends to the dwarf-galaxy regime. I verify that $\omega$Cen (GSE), as well as other NSCs with candidate IMBHs and ultracompact dwarf galaxies, also follow the ${\mathrm{M}}_{\mathrm{BH}}-{\sigma }_{\star }$ relation with stellar velocity dispersion. Under the assumption of a direct collapse BH, $\omega$Cen/GSE's IMBH would require a low initial mass ($\lesssim$10,000 ${\mathrm{M}}_{\odot }$) and almost no accretion over $\sim$3 Gyr, which could be the extreme opposite of high-$z$ galaxies with overmassive BHs such as GN-z11. If $\omega$Cen/GSE's IMBH formed from a Population III supernova remnant, then it could indicate that both light and heavy seeding mechanisms of central BH formation are at play. Other stripped NSCs and dwarf galaxies could help further populate the ${\mathrm{M}}_{\mathrm{BH}}-{\mathrm{M}}_{\star }$ and ${\mathrm{M}}_{\mathrm{BH}}-{\sigma }_{\star }$ relations in the low-mass regime and constraint IMBH demographics and their formation channels.

Accepted to AAS journals

References in corpus (35)

• The Gaia mission
• The Assembly of the First Massive Black Holes
• Evidence from the H3 Survey that the Stellar Halo is Entirely Comprised of Substructure
• Nuclear Star Clusters
• JADES. The diverse population of infant Black Holes at 4<z<11: merging, tiny, poor, but mighty
• The evolution of massive black hole seeds
• A Supermassive Black Hole in an Ultracompact Dwarf Galaxy
• Black Holes on FIRE: Stellar Feedback Limits Early Feeding of Galactic Nuclei
• Kraken reveals itself -- the merger history of the Milky Way reconstructed with the E-MOSAICS simulations
• Gemini and Hubble Space Telescope Evidence for an Intermediate Mass Black Hole in omega Centauri
• The nucleus of the Sagittarius dSph galaxy and M54: a window on the process of galaxy nucleation
• Evidence from APOGEE for the presence of a major building block of the halo buried in the inner Galaxy
• JWST CEERS & JADES Active Galaxies at z = 4-7 Violate the Local $M_{\bullet }-M_{\star }$ Relation at $>3\sigma$: Implications for Low-Mass Black Holes and Seeding Models
• Reconstructing the Last Major Merger of the Milky Way with the H3 Survey
• Improved Dynamical Constraints on the Masses of the Central Black Holes in Nearby Low-mass Early-type Galactic Nuclei And the First Black Hole Determination for NGC 205
• Discovery of a dormant 33 solar-mass black hole in pre-release Gaia astrometry
• Sausage & Mash: The dual origin of the Galactic thick disc and halo from the gas-rich Gaia-Enceladus-Sausage merger
• Timing the Early Assembly of the Milky Way with the H3 Survey
• Fast-moving stars around an intermediate-mass black hole in Omega Centauri
• A new channel to form IMBHs throughout cosmic time
• Reconstructing the Disrupted Dwarf Galaxy $Gaia$-Sausage/Enceladus Using its Stars and Globular Clusters
• Hunting for Massive Black Holes in Dwarf Galaxies
• The Accreted Nuclear Clusters of the Milky Way
• Dynamical Constraints on The Masses of the Nuclear Star Cluster and Black Hole in the Late-Type Spiral Galaxy NGC 3621
• A 10,000-solar-mass black hole in the nucleus of a bulgeless dwarf galaxy
• A little FABLE: exploring AGN feedback in dwarf galaxies with cosmological simulations
• GASTRO library I: the simulated chemodynamical properties of several GSE-like stellar halos
• Populating the low-mass end of the $M_{\mathrm{BH}}-{\sigma }_{\ast }$ relation
• A Chemical Composition Survey of the Iron-Complex Globular Cluster NGC 6273 (M 19)
• Detection of a $\sim$100,000 M${}_{\odot }$ black hole in M31's most massive globular cluster: A tidally stripped nucleus
• Black Hole Growth and Feedback in Isolated Romulus25 Dwarf Galaxies
• The Next Generation Virgo Cluster Survey. XXXIV. Ultra-Compact Dwarf (UCD) Galaxies in the Virgo Cluster
• A deep view into the nucleus of the Sagittarius Dwarf Spheroidal Galaxy with MUSE. II. Kinematic characterization of the stellar populations
• An evolutionary continuum from nucleated dwarf galaxies to star clusters
• Spectroscopy and photometry of the least-massive Type-II globular clusters: NGC1261 AND NGC6934

Cited by in corpus (1)

• Causal Discovery in Astrophysics: Unraveling Supermassive Black Hole and Galaxy Coevolution