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arXiv · 1811.11907

NGC 300 ULX1: A test case for accretion torque theory

Georgios Vasilopoulos·Frank Haberl·Stefania Carpano·Chandreyee Maitra
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Abstract

NGC 300 ULX1 is a newly identified ultra-luminous X-ray pulsar. The system is associated with the supernova impostor SN 2010da that was later classified as a possible supergiant Be X-ray binary. In this work we report on the spin period evolution of the neutron star based on all the currently available X-ray observations of the system. We argue that the X-ray luminosity of the system has remained almost constant since 2010, at a level above ten times the Eddington limit. Moreover, we find evidence that the spin period of the neutron star evolved from ~126 s down to ~18 s within a period of about 4 years. We explain this unprecedented spin evolution in terms of the standard accretion torque theory. An intriguing consequence for NGC 300 ULX1 is that a neutron star spin reversal should have occurred a few years after the SN 2010da event.

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Georgios Vasilopoulos, Frank Haberl, Stefania Carpano, Chandreyee Maitra. 2018-11-29. NGC 300 ULX1: A test case for accretion torque theory. https://doi.org/10.1051/0004-6361%2F201833442

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