Neutron Star Capture Constraints on Primordial Black Holes

A primordial black hole that passes through a neutron star can lose enough energy, by dynamical friction and by accreting stellar material along its chord, to become gravitationally bound to the star. Once bound, it settles, accretes from within, and destroys the star on a timescale short compared with stellar lifetimes. The headline computed values are: example f at 1e22g = 1.00e+00. All quantities are computed from the stated assumptions; nothing in the study is a measurement, and the full calculation is deposited for independent checking.