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arXiv · 1902.11137

Mass ratio in SS433 revisited

A. M. Cherepashchuk·K. A. Postnov·A. A. Belinski
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Abstract

We revisit the determination of binary mass ratio in the Galactic microquasar SS433 based on recent GRAVITY VLTI measurements of mass and angular momentum outflow through a circumbinary disc. The new observations combined with the constancy of the binary orbital period over $\sim 30$ yrs confirm that the mass ratio in SS433 is $q=M_\mathrm{x}/M_\mathrm{v}\gtrsim 0.6$. For the assumed optical star mass $M_\mathrm{v}$ ranging from $\sim 8$ to 15 $M_\odot$ such a mass ratio suggests a low limit of the compact object mass of $M_\mathrm{x}\sim 5-9 M_\odot$, placing the compact object in SS433 as a stellar-mass black hole.

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A. M. Cherepashchuk, K. A. Postnov, A. A. Belinski. 2019-02-28. Mass ratio in SS433 revisited. https://doi.org/10.1093/mnras%2Fstz610

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