Andrew Washington said:
Well, I do not know. What affects the power output?
The power output can be derived from knowing the total energy of the black holes before the merger, the total energy of the black holes after the merger, and the time it takes for the merger to occur.
The total energy of the black holes before the merger can be taken as the sum of the masses of the black holes multiplied by c^2. The total energy of the single black hole after the merger can be taken as the mass of the resultant black hole times c^2. The difference in energies must be radiated away by the merger, the total radiated energy is the radiated power multiplied by the time of the merger.
The time it takes for the merger to occur is measurable directly by observing the gravitational wave signal.
So given initial and final masses of the black hole pair, and the final mass of the black hole pair, one can estimate the power output. There are some other issues, though, which relate to the angular distribution of the radiated power - it's symmetric around the axis of rotation, but not necessarily spherically symmetric - and the relative orientation of the Ligo receivers to the gravitational wave, which affects how efficient Ligo is at receiving the radiated power.
The initial and final masses of the black hole pair are reported in the Ligo papers, but you probably want to ask the question - how were these masses determined? The first step for answering all the questions is to track down the original Ligo paper(s) themselves, and read them. I believe the september 14 observation was the first observed gravitational wave, which is good - you only need to track down and read the papers on the original observation. It will perhaps be useful to track down other papers and commentary, but finding the original source of the Ligo team would be an excellent first step. Have you done this?
