SIMBAD references

About 12 years of photometric monitoring of 65 nova-like cataclysmic variables (CVs) have allowed analysis of occasional VY Sculptoris-type low states, which we define as a fading of more than 1.5 mag in less than 150 days. Detailed light curves of eight systems exhibiting these low states are presented and discussed. The data are sufficient to measure the speeds and the shapes of 29 transitions to and from the low state: both single-slope and dual-slope rises and falls are found, with the dual-sloped transitions always being faster when fainter. This behavior is consistent with the low states being due to a starspot on the secondary star, drifting under the inner Lagrangian point, if the two slopes are interpreted as being due to the passage of the umbral and penumbral portions of the starspot.