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arXiv · 1905.03740

NGC 300 ULX1: spin evolution, super-Eddington accretion and outflows

G. Vasilopoulos·M. Petropoulou·F. Koliopanos·P. S. Ray·C. D. Bailyn·F. Haberl·K. Gendreau
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Abstract

NGC300 ULX1 is an ultra-luminous X-ray pulsar, showing an unprecedented spin evolution, from about 126 s to less than 20 s in only 4 years, consistent with steady mass accretion rate. Following its discovery we have been monitoring the system with Swift/XRT and NICER to further study its properties. We found that even though the observed flux of the system dropped by a factor of $\gtrsim$20, the spin-up rate remained almost constant. A possible explanation is that the decrease in the observed flux is a result of increased absorption of obscuring material due to outflows or a precessing accretion disk.

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G. Vasilopoulos, M. Petropoulou, F. Koliopanos, P. S. Ray, C. D. Bailyn, F. Haberl, K. Gendreau. 2019-05-09. NGC 300 ULX1: spin evolution, super-Eddington accretion and outflows. https://doi.org/10.1093/mnras%2Fstz2045

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