Statistical estimates and physics of close binary systems (CBS) of neutron stars

After some statistical considerations about the number of CBSs with one neutron star in our galaxy, we study the possible kinds of emission of CBSs with two neutron stars. Section 2 contains considerations on the dimension of such a system at the moment of its formation. From the comparison of different kinds of power emitted we deduce that the orbital gravitational emissionP _go dominates. The dynamical evolution of the orbital elementsa ande is determined byP _go and by tidal friction, which produce opposite effects. The quantitative comparison betweenP _goandP _tf (work made per unit time by tidal torque) says thatP _go>P _tf. Therefore we conclude that it isa<0 ande<0; that is the evolution of the systems is towards the collapse.