INTRINSIC KICKS AT BIRTH ARE REQUIRED TO EXPLAIN THE OBSERVED PROPERTIES OF SINGLE AND BINARY NEUTRON-STARS

The single assumption that neutron stars receive a kick, velocity at t heir formation explains a large variety of observations, ranging from observed properties of individual binary radio pulsars and Be/X-ray bi naries to the observed birth rates and dynamical properties of the pop ulations of low-mass X-ray binaries and recycled radio pulsars. The re jection of this one assumption by Iben & Tutukov compels them to intro duce a considerable number of ad hoc hypotheses, each explaining a onl y small part of the observational results. We conclude that the choice of the single powerful assumption that neutron stars receive a kick v elocity at their formation is highly preferable.