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arXiv · 1302.4286

Indications for a slow rotator in the Rapid Burster from its thermonuclear bursting behaviour

T. Bagnoli·J. J. M. in 't Zand·D. K. Galloway·A. L. Watts
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Abstract

We perform time-resolved spectroscopy of all the type I bursts from the Rapid Burster (MXB 1730-335) detected with the Rossi X-ray Timing Explorer. Type I bursts are detected at high accretion rates, up to \sim 45% of the Eddington luminosity. We find evidence that bursts lacking the canonical cooling in their time-resolved spectra are, none the less, thermonuclear in nature. The type I bursting rate keeps increasing with the persistent luminosity, well above the threshold at which it is known to abruptly drop in other bursting low-mass X-ray binaries. The only other known source in which the bursting rate keeps increasing over such a large range of mass accretion rates is the 11 Hz pulsar IGR J17480$-$2446. This may indicate a similarly slow spin for the neutron star in the Rapid Burster.

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T. Bagnoli, J. J. M. in 't Zand, D. K. Galloway, A. L. Watts. 2013-02-18. Indications for a slow rotator in the Rapid Burster from its thermonuclear bursting behaviour. https://doi.org/10.1093/mnras%2Fstt312

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