Peculiar outbursts of an ultra luminous source likely signs of an aperiodic disc-wind
arXiv:1905.05773 · doi:10.3847/1538-4357/ab1e4b
Abstract
The metal rich globular cluster RZ 2109 in the massive Virgo elliptical galaxy NGC 4472 (M49) harbours the ultra luminous X-ray source XMMU 122939.7+075333. Previous studies showed that this source varies between bright and faint phases on timescales of just a few hours. Here, we report the discovery of two peculiar X-ray bursting events that last for about 8 and 3.5 hours separated by about 3 days. Such a recurring X-ray burst-like behaviour has never been observed before. We argue that type-I X-ray bursts or super bursts as well as outburst scenarios requiring a young stellar object are highly unlikely explanations for the observed light curve, leaving an aperiodic disc wind scenario driven by hyper-Eddington accretion as a viable explanation for this new type of X-ray flaring activities.
7 pages, 2 figures, accepted by ApJ
References in corpus (8)
- An Ultraluminous X-ray Source Powered by An Accreting Neutron Star
- SMC X-3: the closest ultraluminous X-ray source powered by a neutron star with non-dipole magnetic field
- Ensemble X-ray variability of Active Galactic Nuclei. II. Excess Variance and updated Structure Function
- Ultraluminous X-ray bursts in two ultracompact companions to nearby elliptical galaxies
- Very Broad [O III]4959,5007 Emission from the NGC 4472 Globular Cluster RZ2109 and Implications for the Mass of Its Black Hole X-ray Source
- Multi-epoch spectroscopy of the globular cluster black hole in NGC 4472
- The superburst recurrence time in luminous persistent LMXBs
- Deep observations of the NGC 4472 globular cluster black hole XMMU 122939.7+075333: Short term variability from the first globular cluster black hole binary