Spectroscopic and photometric observations of the short-period RS CVn-type star UV Piscium

High-resolution spectroscopic observations around the Ha line and long-term BVRI photometry of the eclipsing short-period RS CVn star UV Psc are presented. The simultaneous solution of our radial velocity curves and light curves yields the following values for the global parameters of the components: M-1 = 1.1 M-circle dot, M-2 = 0.81 M-circle dot, R-1 = 1.14 R-circle dot and R-2 = 0.85 R-circle dot. The measured rotational broadening of the spectral lines corresponds to equatorial velocities V-1 = 68.3 and V-2 = 53.3 km s(-1). Our spectral data reveal high activity of the two stellar components and very fast variability of the Ha line in the center of the primary eclipse. Modeling our photometric data shows trends in the starspot behavior. The trend toward active longitude belts can have occasional exceptions. The observed secular luminosity decrease in 1999 may signal the onset of a new magnetic activity cycle.