http://arxiv.org/abs/2002.07852
We present the serendipitous discovery of a low luminosity nova occurring in a symbiotic binary star system in the Milky Way. We lay out the extensive archival data alongside new follow-up observations related to the stellar object V$^$ CN Cha in the constellation of Chamaeleon. The object had long period ($\sim! 250\,$day), high amplitude ($\sim! 3\,$mag) optical variability in its recent past, preceding an increase in optical brightness by $\sim! 8\,$magnitudes and a persistence at this luminosity for about 3 years, followed by a period of $\sim! 1.4\,{\rm mag}\,{\rm yr}^{-1}$ dimming. The object’s current optical luminosity seems to be dominated by H$\alpha$ emission, which also exhibits blue-shifted absorption (a P-Cygni-like profile). After consideration of a number of theories to explain these myriad observations, we determine that V$^$ CN Cha is most likely a symbiotic (an evolved star-white dwarf binary) system which has undergone a long-duration, low luminosity, nova. Interpreted in this way, the outburst in V$^*$ CN Cha is among the lowest luminosity novae ever observed.
L. Lancaster, J. Greene, Y. Ting, et. al.
Thu, 20 Feb 20
38/61
Comments: Submitted to AJ, 19 pages, 9 figure