  Primordial stars are likely to be very massive >30 Msun, form in isolation,
and will likely leave black holes as remnants in the centers of their host dark
matter halos. We expect primordial stars to form in halos in the mass range
10^6-10^10 Msun. Some of these early black holes, formed at redshifts z>10,
could be the seed black hole for a significant fraction of the supermassive
black holes found in galaxies in the local universe. If the black hole
descendants of the primordial stars exist, their mergers with nearby
supermassive black holes may be a prime candidate for long wavelength
gravitational wave detectors. We simulate formation and evolution of dark
matter halos in LambdaCDM universe. We seed high-redshift dark matter halos
with early black holes, and explore the merger history of the host halos and
the implications of black hole's kick velocities arising from their
coalescence. The central concentration of low mass early black holes in present
day galaxies is reduced if they experience even moderate kicks of tens of km/s.
Even such modest kicks allow the black holes to leave their parent halo, which
consequently leads to dynamical friction being less effective on the low mass
black holes that were ejected, compared to those still embedded in their parent
halos. Therefore, merger rates with central supermassive black holes in the
largest halos may be reduced by more than an order of magnitude. Using
analytical and illustrative cosmological N-body simulations, we quantify the
role of kicks on the merger rates of black holes formed from massive metal free
stars with supermassive black holes in present day galaxies.
