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arXiv · 2101.01569

Radio flaring and dual radio loud/quiet behaviour in the new candidate black hole X-ray binary MAXI J1631-472

Itumeleng M. Monageng·Sara E. Motta·Rob Fender·Wenfei Yu·Patrick A. Woudt·Evangelia Tremou·James C. A. Miller-Jones·Alexander J. van der Horst
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Abstract

We present the results of a weekly monitoring of the new black hole candidate X-ray binary MAXI J1631-472 carried out with the MeerKAT radio interferometer, the Neil Gehrels Swift Observatory, and the Monitor of All-sky X-ray Image (MAXI) instrument, during its 2018-2019 outburst. The source exhibits a number of X-ray states, in particular both high- and low-luminosity hard states bracketed by extended soft states. Radio flaring is observed shortly after a transition from hard/intermediate states to the soft state. This is broadly in agreement with existing empirical models, but its extended duration hints at multiple unresolved flares and/or jet-ISM interactions. In the hard state radio:X-ray plane, the source is revealed to be 'radio quiet' at high luminosities, but to rejoin the `standard' track at lower luminosities, an increasingly commonly-observed pattern of behaviour.

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Itumeleng M. Monageng, Sara E. Motta, Rob Fender, Wenfei Yu, Patrick A. Woudt, Evangelia Tremou, James C. A. Miller-Jones, Alexander J. van der Horst. 2021-01-04. Radio flaring and dual radio loud/quiet behaviour in the new candidate black hole X-ray binary MAXI J1631-472. https://doi.org/10.1093/mnras%2Fstab043

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