Songlines from Direct Collapse Seed Black Holes: Effects of X-rays on
  Black Hole Growth and Stellar Populations
  In the last decade, the growth of supermassive black holes (SMBHs) has been
intricately linked to galaxy formation and evolution and is a key ingredient in
the assembly of galaxies. To investigate the origin of SMBHs, we perform
cosmological simulations that target the direct collapse black hole (DCBH) seed
formation scenario in the presence of two different strong Lyman-Werner (LW)
background fields. These simulations include the X-ray irradiation from a
central massive black hole (MBH), $\rm{H}_2$ self-shielding and stellar
feedback from metal-free and metal-enriched stars. We find in both simulations
that local X-ray feedback induces metal-free star formation $\sim 0.5$ Myr
after the MBH forms. The MBH accretion rate reaches a maximum of $10^{-3}$
$M_{\odot}$ yr$^{-1}$ in both simulations. However, the duty cycle differs
which is derived to be $6\%$ and $50\%$ for high and low LW cases,
respectively. The MBH in the high LW case grows only $\sim 6\%$ in 100 Myr
compared to $16\%$ in the low LW case. We find that the maximum accretion rate
is determined by the local gas thermodynamics whereas the duty cycle is
determined by the large scale gas dynamics and gas reservoir. We conclude that
radiative feedback from the central MBH plays an important role in star
formation in the nuclear regions and stifling initial MBH growth, relative to
the typical Eddington rate argument, and that initial MBH growth might be
affected by the local LW radiation field.
