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arXiv · 2107.01149

Beamed emission from a neutron-star ULX in a GRRMHD simulation

David Abarca·Kyle Parfrey·Włodek Kluźniak
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Abstract

We perform a global 2.5D general-relativistic radiation magnetohydrodynamic simulation of super-critical accretion onto a neutron star with a $2\times 10^{10}$ G dipolar magnetic field, as a model of a neutron-star-powered ultraluminous X-ray source (ULX). We compute a lower limit on the total luminosity of $\sim 2.5\,L_\mathrm{Edd}$, and find the radiation to be highly beamed by the accretion disk outflows. The apparent isotropic luminosity, which is a function of the viewing angle, reaches a maximum above $100\,L_\mathrm{Edd}$, consistent with the luminosities observed in ULXs.

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David Abarca, Kyle Parfrey, Włodek Kluźniak. 2021-07-02. Beamed emission from a neutron-star ULX in a GRRMHD simulation. https://doi.org/10.3847/2041-8213/ac1859

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