Aydi, E.Sokolovsky, K. V.Bright, J. S.Tremou, E.Nyamai, M. M.Evans, A.Strader, J.Chomiuk, L.Myers, G.Hambsch, F-J.Page, K. L.Buckley, D. A. H.Woodward, C. E.Walter, F. M.Mróz, P.Vallely, P. J.Geballe, T. R.Banerjee, D. P. K.Gehrz, R. D.Fender, R. P.Gromadzki, M.Kawash, A.Knigge, C.Mukai, K.Munari, U.Orio, M.Ribeiro, V. A. R. M.Sokoloski, J. L.Starrfield, S.Udalski, A.Woudt, P. A.2021-09-152021-09-152021-08-17http://hdl.handle.net/11603/22990We present a detailed study of the 2019 outburst of the cataclysmic variable V1047 Cen, which hosted a classical nova eruption in 2005. The peculiar outburst occurred 14 years after the classical nova event, lasted for more than 400 days, and reached an amplitude of around 6 magnitudes in the optical. Early spectral follow-up revealed what could be a dwarf nova (accretion disk instability) outburst in a classical nova system. However, the outburst duration, high velocity (>2000 km s⁻¹) features in the optical line profiles, luminous optical emission, and the presence of prominent long-lasting radio emission, together suggest a phenomenon more exotic and energetic than a dwarf nova outburst. There are striking similarities between this V1047 Cen outburst and those of "combination novae" in classical symbiotic stars. We suggest that the outburst may have started as a dwarf nova that led to the accretion of a massive disk, which in turn triggered enhanced nuclear shell burning on the white dwarf and eventually led to generation of a wind/outflow. From optical photometry we find a \bf{possible} orbital period of 8.36 days, which supports the combination nova scenario and makes the system an intermediate case between typical cataclysmic variables and classical symbiotic binaries. If true, such a phenomenon would be the first of its kind to occur in a system that has undergone a classical nova eruption and is intermediate between cataclysmic variables and symbiotic binaries.36 pagesen-USThis item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.Attribution 4.0 International (CC BY 4.0)Text