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arXiv · 2308.04104

Pre-outburst signal in the light curves of the recurrent novae RS Oph and T CrB

R. K. Zamanov·V. Marchev·J. Marti·G. Y. Latev
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Abstract

Pre-outburst signal (a decrease of the optical brightness) just before the outburst is clearly detected in the observations of the T CrB obtained before and during the 1946 outburst. A similar decrease is also visible in the light curve of RS Oph during the 2021 outburst. We suppose that this is due to formation of a thick, dense envelope around the white dwarf, and we estimate its size (1000 - 2000 km), mass (5.10$^{-8}$ - 6.10$^{-7}$ M$_\odot$) and average density (5 - 16 g cm$^{-3}$).

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R. K. Zamanov, V. Marchev, J. Marti, G. Y. Latev. 2023-08-08. Pre-outburst signal in the light curves of the recurrent novae RS Oph and T CrB. https://arxiv.org/abs/2308.04104

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