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arXiv · 2007.13775

Discovery of optical outflows and inflows in the black hole candidate GRS 1716-249

V. A. Cúneo·T. Muñoz-Darias·J. Sánchez-Sierras·F. Jiménez-Ibarra·M. Armas Padilla·D. A. H. Buckley·J. Casares·P. Charles·J. M. Corral-Santana·R. Fender·J. A. Fernández-Ontiveros·D. Mata Sánchez·G. Panizo-Espinar·G. Ponti·M. A. P. Torres
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Abstract

We present optical spectroscopy obtained with the GTC, VLT and SALT telescopes during the decline of the 2016-2017 outburst of the black hole candidate GRS 1716-249 (Nova Oph 1993). Our 18-epoch data set spans 6 months and reveals that the observational properties of the main emission lines are very variable, even on time scales of a few hours. Several epochs are characterised by P-Cyg (as well as flat-top and asymmetric) profiles in the H$\alpha$, H$\beta$ and He II ($\lambda$4686) emission lines, implying the presence of an accretion disc wind, which is likely hot and dense. The wind's terminal velocity ($\sim$2000 km s$^{-1}$) is similar to that observed in other black hole X-ray transients. These lines also show transient and sharp red-shifted absorptions, taking the form of inverted P-Cyg profiles. We argue that these profiles can be explained by the presence of infalling material at $\sim$1300 km s$^{-1}$. We propose a failed wind scenario to explain this inflow and discuss other alternatives, such as obscuration produced by an accretion-related structure (e.g. the gas stream) in a high inclination system.

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V. A. Cúneo, T. Muñoz-Darias, J. Sánchez-Sierras, F. Jiménez-Ibarra, M. Armas Padilla, D. A. H. Buckley, J. Casares, P. Charles, J. M. Corral-Santana, R. Fender, J. A. Fernández-Ontiveros, D. Mata Sánchez, G. Panizo-Espinar, G. Ponti, M. A. P. Torres. 2020-07-27. Discovery of optical outflows and inflows in the black hole candidate GRS 1716-249. https://doi.org/10.1093/mnras%2Fstaa2241

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