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

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 $\sim 2.5L_{\mathrm{Edd}}$, 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 $100L_{\mathrm{Edd}}$, consistent with the luminosities observed in ULXs.

9 pages, 4 figures, Submitted to ApJ Letters

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Cited by in corpus (4)

• Bright X-ray Pulsars: how outflows influence beaming, pulsations and pulse phase lags
• Populations of Neutron Star Ultraluminous X-ray Sources: Mind your b's and B's
• Two-temperature accretion flows around strongly magnetized stars and their spectral analysis
• Energy flow and radiation efficiency in radiative GRMHD simulations of neutron star ultraluminous X-ray sources