  In a recent letter we have outlined some issues on GW 150914, we hereby give
additional details. We analyze the event GW 150914 announced by the Advanced
Laser Interferometer Gravitational-Wave Observatory (LIGO) as the
gravitational-wave emission of a black-hole binary merger. We show that the
parameters of the coalescing system and of the newly formed Kerr black-hole can
be extracted from basic results of the gravitational-wave emission during the
inspiraling and merger phases without sophisticate numerical simulations. Our
strikingly accurate estimates are based on textbook formulas describing two
different regimes: 1) the binary inspiraling analysis treated in Landau and
Lifshitz textbook, 2) the plunge of a particle into a black-hole, treated in
the Rees-Ruffini-Wheeler textbook as well as 3) the transition between these
two regimes following Detweiler's treatment of a particle infalling with
non-zero angular momentum onto a black-hole. It is stressed that in order to
infer any astrophysical information on the masses of the system both regimes
have to be independently and observationally constrained by LIGO, which does
not appear to be the case.
