Hunting A Wandering Supermassive Black Hole in M31 Halo -- Hermitage of Black Hole

Abstract

In the hierarchical structure formation scenario, galaxies enlarge through multiple merging events with less massive galaxies. In addition, the Magorrian relation indicates that almost all galaxies are occupied by a central supermassive black hole (SMBH) of mass $10^{-3}$ of its spheroidal component. Consequently, SMBHs are expected to wander in the halos of their host galaxies following a galaxy collision, although evidence of this activity is currently lacking. We investigate a current plausible location of an SMBH wandering in the halo of the Andromeda galaxy (M31). According to theoretical studies of $N$-body simulations, some of the many substructures in the M31 halo are remnants of a minor merger occurring about 1 Gyr ago. First, to evaluate the possible parameter space of the infalling orbit of the progenitor, we perform numerous parameter studies using a Graphics Processing Unit (GPU) cluster. To reduce uncertainties in the predicted position of the expected SMBH, we then calculate the time evolution of the SMBH in the progenitor dwarf galaxy from $N$-body simulations using the plausible parameter sets. Our results show that the SMBH lies within the halo ($\sim$20--50 kpc from the M31 center), closer to the Milky Way than the M31 disk. Furthermore, the predicted current positions of the SMBH were restricted to an observational field of $0\degr.6 \times 0\degr.7$ in the northeast region of the M31 halo. We also discuss the origin of the infalling orbit of the satellite galaxy and its relationships with the recently discovered vast thin disk plane of satellite galaxies around M31.

10 pages, 4 figures, accepted for publication in ApJ. Online-only materials are available at: http://www.ccs.tsukuba.ac.jp/Astro/Members/ymiki/gallery.html

References in corpus (11)

• A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy
• The Haunted Halos of Andromeda and Triangulum: A panorama of galaxy formation in action
• The M31 Velocity Vector. II. Radial Orbit Towards the Milky Way and Implied Local Group Mass
• The Metal-Poor Halo of the Andromeda Spiral Galaxy (M31)
• Investigating the Andromeda Stream: III. A Young Shell System in M31
• The M31 Velocity Vector. I. Hubble Space Telescope Proper Motion Measurements
• Wandering Black Holes in Bright Disk Galaxy Halos
• Incorporating interactive 3-dimensional graphics in astronomy research papers
• Stellar Kinematics in the Complicated Inner Spheroid of M31: Discovery of Substructure Along the Southeastern Minor Axis and its Relationship to the Giant Southern Stream
• The Once and Future Andromeda Stream
• An Advanced, Three-Dimensional Plotting Library for Astronomy

Cited by in corpus (11)

• The (black hole)-bulge mass scaling relation at low masses
• Feedback by Massive Black Holes in Dwarf Galaxies
• From galactic nuclei to the halo outskirts: tracing supermassive black holes across cosmic history and environments
• Formation of the Andromeda Giant Stream: Asymmetric Structure and Disc Progenitor
• Advanced Data Visualization in Astrophysics: the X3D Pathway
• Collision tomography: Physical properties of possible progenitors of the Andromeda stellar stream
• Puzzling Outer-Density Profile of the Dark Matter Halo in the Andromeda Galaxy
• Statistical properties of substructures around Milky Way-sized haloes and their implications for the formation of stellar streams
• Relics of Galaxy Merging: Observational Predictions for a Wandering Massive Black Hole and Accompanying Star Cluster in the Halo of M31
• Destruction of the central black hole gas reservoir through head-on galaxy collisions
• The origin of the black hole offset in M31