Is the Symbiotic Recurrent Nova T CrB Late? Recent Photometric Evolution and Comparison with Past Pre-Outburst Behaviour
astro-ph.SR
/ Authors
Jaroslav Merc, Łukasz Wyrzykowski, Paul G. Beck, Przemysław J. Mikołajczyk, Krzysztof Kotysz, Paweł Zieliński, Staszek Zola, Sebastian Kurowski, Waldemar Ogłoza, Marek Drozdz
and 39 more authors
Charles Galdies, Franz-Josef Hambsch, Stephen M. Brincat, Barbara Joachimczyk, Mateusz Bronikowski, Jure Japelj, Matej Mihelcic, Josep Manel Carrasco, Umut Burgaz, Agnieszka Gurgul, Karolina Bąkowska, Piotr Hofbauer, Krzysztof Szyszka, Jan Golonka, Jan Kåre Trandem Qvam, Justas Zdanavičius, Erika Pakštienė, Marius Maskoliūnas, Vytautas Čepas, Uliana Pylypenko, Dawid Moździerski, Franky Dubois
/ Abstract
T CrB is a symbiotic recurrent nova that last erupted in 1946. Given its recurrence timescale of approximately 80 years, the next outburst is eagerly anticipated by the astronomical community. In this work, we analyse the optical light curves of T CrB, comparing recent photometric evolution with historical data to evaluate potential predictive indicators of nova eruptions. Although the "super-active" phases preceding both the 1946 and anticipated eruptions are strikingly similar, the subsequent photometric behaviour differs. We find that the decline in brightness observed in 2023, interpreted by some as a "pre-eruption dip", deviates from the deep minimum recorded prior to the 1946 event and does not reliably predict the eruption timing. Recent photometric and spectroscopic observations indicate that the system is returning to a high-accretion state. Given this, an eruption may be imminent, even without distinct precursors. While the next eruption of T CrB will be a major scientific event, its expected peak brightness of $V \sim 2$ mag highlights the importance of setting realistic public expectations for what will be a visually modest, yet astrophysically very significant, celestial event.