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Evolution of Binary Compact Objects Which Merge

Hans A. Bethe·G. E. Brown
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Abstract

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.

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Hans A. Bethe, G. E. Brown. 1998-04-07. Evolution of Binary Compact Objects Which Merge. https://doi.org/10.1086/306265

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