Quote from Tony on 09/22/14 at 06:38:58:Compute the center of mass of the binary. Pretend all the mass was there, and treat it as a single object. Now see if energy is negative, or check if ecc < 1 or sma is positive.
Thanks Tony , you think treating the binary at its COG gives better results than taking account of the two seperate masses ?
I think in general yes it is but :
If COG is used one does not take into account a change in energy due to a close encounter of one part of the binary .
I'm not very sure in this case .
Is there a way to test in GravSim the result if I would test the second approach ?