Evolution of Binary Compact Objects Which Merge
Abstract
Description
Beginning from massive binaries in the Galaxy we evolve black-hole, neutron-star binaries and binary neutron stars, such as the Hulse-Taylor system PSR 1913+16. The new point in our evolution is a quantitative calculation of the accretion of matter by a neutron star in common envelope evolution which sends it into a black hole. We calculate the mass of the latter to be $\sim 2.4\msun$.
Our chief conclusion is that the production rate for black-hole, neutron-star binaries (in which the neutron star is unrecycled) is $\sim 10^{-4}$ per year per Galaxy, an order of magnitude greater than that of neutron star binaries. Not only should this result in a factor of $\sim$ 10 more mergings for gravitational wave detectors like LIGO, but the signal should be larger.
We give some discussion of why black-hole, neutron-star binaries have not been observed, but conclude that they should be actively searched for.
32 pages, no figures Replacement is final version as accepted by The Astrophysical Journal
32 pages, no figures Replacement is final version as accepted by The Astrophysical Journal