Possibility of primordial black holes as the source of gravitational
  wave events in the advanced LIGO detector
  The analysis of gravitational Wave (GW) data from advanced LIGO provides the
mass of each companion of binary black holes as the source of GWs. The mass of
events corresponding to the binary black holes from GW is above $20$ M$_\odot$
which is much larger than the mass of astrophysical black holes detected by
x-ray observations. In this work, we examine primordial black holes (PBHs) as
the source of LIGO events. Assuming that $100\%$ of the dark matter is made of
PBHs, we estimate the rate at which these objects make binaries, merge, and
produce GWs as a function of redshift. The gravitational lensing of GWs by PBHs
can also enhance the amplitude of the strain. We simulate GWs sourced by binary
PBHs, with the detection threshold of $S/N>10$ for both Livingston and Hanford
detectors. For the log-normal mass function of PBHs, we generate the expected
distribution of events, compare our results with the observed events, and find
the best value of the mass function parameters (i.e., $M_c =25 M_\odot$ and
$\sigma=0.6$) in the log-normal mass function. Comparing the expected number of
events with the number of observed ones rules out the present-Universe binary
formation PBH scenario as the candidate for the source of GW events detected by
LIGO.
