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arXiv · 2412.01797

The Newly Discovered Nova Super-Remnant Surrounding Recurrent Nova T Coronae Borealis: Will it Light Up During the Coming Eruption?

Michael M. Shara·Kenneth M. Lanzetta·Alexandra Masegian·James T. Garland·Stefan Gromoll·Joanna Mikolajewska·Mikita Misiura·David Valls-Gabaud·Frederick M. Walter·John K. Webb
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Abstract

A century or less separates the thermonuclear-powered eruptions of recurrent novae in the hydrogen-rich envelopes of massive white dwarfs. The colliding ejecta of successive recurrent nova events are predicted to always generate very large (tens of parsecs) super-remnants; only two examples are currently known. T CrB offers an excellent opportunity to test this prediction. As it will almost certainly undergo its next, once-in ~80-year recurrent nova event between 2024 and 2026, we carried out very deep narrowband and continuum imaging to search for the predicted, piled-up ejecta of the past millenia. While nothing is detected in continuum or narrowband [OIII] images, a ~30-parsec-diameter, faint nebulosity surrounding T CrB is clearly present in deep Halpha, [NII] and [SII] narrowband Condor Array Telescope imagery. We predict that these newly detected nebulosities, as well as the recent ejecta that have not yet reached the super-remnant, are far too optically-thin to capture all but a tiny fraction of the photons emitted by RN flashes. We thus predict that fluorescent light echoes will NOT be detectable following the imminent nova flash of T CrB. Dust may be released by the T CrB red giant wind in pre-eruption outbursts, but we have no reliable estimates of its quantity or geometrical distribution. While we cannot predict the morphology or intensity of dust-induced continuum light echoes following the coming flash, we encourage multi-epoch Hubble Space Telescope optical imaging as well as James Webb Space Telescope infrared imaging of T CrB during the year after it erupts.

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Michael M. Shara, Kenneth M. Lanzetta, Alexandra Masegian, James T. Garland, Stefan Gromoll, Joanna Mikolajewska, Mikita Misiura, David Valls-Gabaud, Frederick M. Walter, John K. Webb. 2024-12-02. The Newly Discovered Nova Super-Remnant Surrounding Recurrent Nova T Coronae Borealis: Will it Light Up During the Coming Eruption?. https://arxiv.org/abs/2412.01797

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