The Bursting Pulsar GRO J1744-28: the Slowest Transitional Pulsar?

TL;DR

This paper suggests that GRO J1744-28, known as the Bursting Pulsar, exhibits variability similar to Transitional Millisecond Pulsars, implying it may be a transitional pulsar with unique properties, offering new insights into pulsar evolution.

Contribution

It proposes that the Bursting Pulsar is a transitional pulsar, expanding the class to include systems with higher spin periods and magnetic fields, and explores the implications of this identification.

Findings

Variability in GRO J1744-28 is analogous to that in Transitional Millisecond Pulsars.

GRO J1744-28 may be a transitional pulsar with higher spin period and magnetic field.

This identification opens new avenues for studying pulsar evolution in unexplored regimes.

Abstract

GRO J1744-28 (the Bursting Pulsar) is a neutron star LMXB which shows highly structured X-ray variability near the end of its X-ray outbursts. In this letter we show that this variability is analogous to that seen in Transitional Millisecond Pulsars such as PSR J1023+0038: 'missing link' systems consisting of a pulsar nearing the end of its recycling phase. As such, we show that the Bursting Pulsar may also be associated with this class of objects. We discuss the implications of this scenario; in particular, we discuss the fact that the Bursting Pulsar has a significantly higher spin period and magnetic field than any other known Transitional Pulsar. If the Bursting Pulsar is indeed transitional, then this source opens a new window of opportunity to test our understanding of these systems in an entirely unexplored physical regime.