A New Class of Radio Pulsars - Back in 1982

TL;DR

This paper discusses the evolution of neutron stars into millisecond radio pulsars through accretion in X-ray binaries, highlighting the discovery of low magnetic fields and the connection between X-ray and radio pulsars.

Contribution

It introduces the concept of a new class of radio pulsars spun up by accretion, linking X-ray millisecond pulsars with radio millisecond pulsars and explaining their low magnetic fields.

Findings

Discovery of millisecond pulsars with low magnetic fields.

Confirmation of predicted spin-down rates of millisecond pulsars.

Identification of X-ray millisecond pulsars and their relation to radio pulsars.

Abstract

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.