BVRI photom. of DV Psc and known short-period EBs

Using 27 sets of new multiband photometry light curves acquired from our long-term photometric campaign carried out in the last 5yr and high-resolution spectroscopic data from seven nights, we analyzed the physical mechanisms of period variation, starspot cycle, optical flares, and chromospheric activities of the eclipsing binary DV Psc. Our updated O-C diagram covering a period of approximately 20yr shows an oscillation in its orbital period.

This variations might be caused by a third body with an orbital period of 14.58+/-0.28yr. There are two active regions of starspots at longitude belts of about 90{deg} and 270{deg}. We obtained its starspot cycles with periods of 3.60+/-0.03yr and 3.42+/-0.02yr at about 90{deg} and 270{deg}, respectively.