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arXiv · 1808.06916

The Evolution of X-ray Bursts in the "Bursting Pulsar" GRO J1744-28

J. M. C. Court·D. Altamirano·A. C. Albayati·A. Sanna·T. Belloni·T. Overton·N. Degenaar·R. Wijnands·K. Yamaoka·A. B. Hill·C. Knigge
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Abstract

GRO J1744-28, commonly known as the `Bursting Pulsar', is a low mass X-ray binary containing a neutron star and an evolved giant star. This system, together with the Rapid Burster (MXB 1730-33), are the only two systems that display the so-called Type II X-ray bursts. These type of bursts, which last for 10s of seconds, are thought to be caused by viscous instabilities in the disk; however the Type II bursts seen in GRO J1744-28 are qualitatively very different from those seen in the archetypal Type II bursting source the Rapid Burster. To understand these differences and to create a framework for future study, we perform a study of all X-ray observations of all 3 known outbursts of the Bursting Pulsar which contained Type II bursts, including a population study of all Type II X-ray bursts seen by RXTE. We find that the bursts from this source are best described in four distinct phenomena or `classes' and that the characteristics of the bursts evolve in a predictable way. We compare our results with what is known for the Rapid Burster and put out results in the context of models that try to explain this phenomena.

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J. M. C. Court, D. Altamirano, A. C. Albayati, A. Sanna, T. Belloni, T. Overton, N. Degenaar, R. Wijnands, K. Yamaoka, A. B. Hill, C. Knigge. 2018-08-21. The Evolution of X-ray Bursts in the "Bursting Pulsar" GRO J1744-28. https://doi.org/10.1093/mnras%2Fsty2312

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