TITLE:
N-Body Simulations of Gas-Free Disc Galaxies with SMBH Seed in Binary Systems
AUTHORS:
R. Chan
KEYWORDS:
Simulation, Disc Galaxy, Supermassive Black Hole, Binary Galaxies, Merger, Warped Disc Galaxies
JOURNAL NAME:
International Journal of Astronomy and Astrophysics,
Vol.9 No.3,
July
9,
2019
ABSTRACT: We have shown the outcome of N-body
simulations of the interactions of two disc galaxies without gas with the same
mass. Both disc galaxies have halos of dark matter, central bulges and initial
supermassive black hole (SMBH) seeds at their centers. The purpose of this work
is to study the mass and dynamical evolution of the initial SMBH seed during a
Hubble cosmological time. It is a complementation of our previous paper with
different initial orbit conditions and by introducing the SMBH seed in the
initial galaxy. The disc of the secondary galaxy has a coplanar or polar
orientation in relation to the disc of the primary galaxy and their initial
orbit are eccentric and prograde. The primary and secondary galaxies have mass
and size of Milky Way with an initial SMBH seed. We have found that the merger
of the primary and secondary discs can result in a final normal disc or a final
warped disc. After the fusion of discs, the final one is thicker and larger
than the initial disc. The tidal effects are very important, modifying the
evolution of the SMBH in the primary and secondary galaxy differently. The mass
of the SMBH of the primary galaxy has increased by a factor ranging from 52 to 64 times the initial seed mass,
depending on the experiment. However, the mass of the SMBH of the secondary
galaxy has increased by a factor ranging from 6 to 33 times the initial SMBH seed
mass, depending also on the experiment. Most of the accreted particles have
come from the bulge and from the halo, depleting their particles. This could
explain why the observations show that the SMBH with masses of approximatelyis found in many bulgeless galaxies. Only a small number of the accreted
particles has come from the disc. In some cases of final merging stage of the
two galaxies, the final SMBH of the secondary galaxy was ejected out of the
galaxy.