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arXiv · 1407.0557

HLX-1 may be an SS433 system

Andrew King·Jean-Pierre Lasota
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Abstract

We show that the hyperluminous source HLX--1 may be a stellar--mass binary system like SS433, but seen along its X--ray beams. The precession of these beams gives the $\sim 1$~yr characteristic timescale of the light curve, while the significant X--ray duty cycle means that the precession angle must be comparable with the beam opening angle, which is of order $1.6^{\circ}$. The X--ray light curve appears to result from geometric collimation and scattering as the beam moves through the line of sight. Encouragingly, the distance $\sim 95$~Mpc suggested for HLX--1 is only a few times larger than the minimum distance at which we can expect to view such a highly--beamed system along its axis. This picture allows a simple interpretation of HLX--1 as the most extreme known member of the ULX population.

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Andrew King, Jean-Pierre Lasota. 2014-07-02. HLX-1 may be an SS433 system. https://doi.org/10.1093/mnrasl/slu105

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