BVRI light curves of Nova V723 Cas

The mean magnitude during this period, stable at ~3mag brighter than in quiescence, and the continuous presence of strong [FeX] and other high-ionization emission lines, indicates that the nuclear burning at the surface of the white dwarf is continuing 20-years past the initial outburst.

The light curve shows a large amplitude (2mag) orbital modulation, which is governed by the visibility of the irradiated side of the secondary star. Our observations do not confirm the reported increase with time of the orbital period of V723 Cas, a period of P=16.638383+/-0.000025h satisfying equally well all available observations in all bands. Our observations also do not confirm the presence of an additional periodicity around P=15.2397h from which V723 Cas was classified as an intermediate-polar system.