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A peculiar type-I X-ray burst from GRS 1747-312

J. J. M. in 't Zand·T. E. Strohmayer·C. B. Markwardt·J. Swank
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Abstract

We report the serendipitous detection with the Rossi X-ray Timing Explorer of a long and peculiar X-ray burst whose localization is consistent with one known X-ray burster (GRS 1747-312) and which occurred when that source was otherwise quiescent. The peculiar feature concerns a strong radius expansion of the neutron star photosphere, which occurred not within a few seconds from the start of the burst, as is standard in radius-expansion bursts, but 20 s later. This suggests that two different layers of the neutron star may have undergone thermonuclear runaways: a hydrogen-rich and a hydrogen-poor layer. The reason for the delay may be related to the source being otherwise quiescent.

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J. J. M. in 't Zand, T. E. Strohmayer, C. B. Markwardt, J. Swank. 2003-07-02. A peculiar type-I X-ray burst from GRS 1747-312. https://doi.org/10.1051/0004-6361%3A20031042

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