Life after eruption - II. The eclipsing old nova V728 Scorpii

The old nova V728 Sco has been recently recovered via photometric and
spectroscopic observations, 150 yr after the nova eruption. The spectral
properties pointed to a high-inclination system with a comparatively low
mass-transfer rate. In this paper, we show that the object is an
eclipsing system with an orbital period of 3.32 h. It has enhanced
long-term variability that can be interpreted as `stunted’
dwarf-nova-type outbursts. Using the ingress and egress times of the
eclipsed components we calculate the radius of the central object. The
latter turns out to be significantly larger than a white dwarf and we
identify it with a hot inner disc. The implications for models on the
behaviour of post-novae are discussed.