A New Class of Radio Pulsars - Back in 1982

Basic ideas about the torques on the neutron star and the existence of an equilibrium rotation period followed from the recognition that most X-ray binaries contain accretion powered neutron stars. The evolution of binaries through a phase of accretion onto the neutron star, eventually leading to a post-accretion radio pulsar phase, was initially discussed as a way to understand the scarcity of binaries among the radio pulsars and the relatively short rotation periods of the first discovered binary radio pulsars in terms of magnetic fields that would be smaller than the familiar $10^{12} G$ range. The discovery of the millisecond pulsars made us realize that the fields can be much lower in a new class of radio pulsars that have been spun up by accretion in LMXBs. The predicted spin-down rates of the millisecond pulsar was soon confirmed. The observers' search for millisecond X-ray periods was on, leading first to the discovery of QPOs, and eventually to the discovery of the X-ray millisecond pulsars. The theorists' quest for explanations of why X-ray millisecond pulsations are not observed from LMXBs also started right away.