Active eclipsing binary RT Andromedae revisited

All available photometric and spectroscopic data of the short-period RS CVn -like binary RT And have been reanalyzed in a homogeneous way. The long-ter m orbital period change is explained by two period jumps, a continuous peri od decrease combined with the light-time orbit or two light-time orbits. UB VRIJK light curves without maculation effects together with the radial velo cities of both components were analysed with the Wilson-Devinney program to compute the photometric and spectroscopic elements and derive the masses o f the components: m(1) = 1.10+/-0.02 M. and m(2) = 0.83+/-0.02 M.. The high orbital inclination i = 87.6 degrees +/- 0.1 degrees was confirmed by phot oelectric observations of the secondary minimum. The mean observed U light curve shows additional light during the secondary minimum. The small eccent ricity found by several authors from the light-curve analysis cannot be rul ed out. The face-to-face position of the spots on the surface of both compo nents in 1971 indicates the possibility of a mass transfer from the primary to the secondary component through a magnetic bridge connecting both activ e regions. Analysis of all available light curves suggests a random positio n of starspots and does not confirm the idea of active longitude belts. The absolute parameters of the binary together with maximal apparent V brightn ess set the distance of RT And to 83+/-2 pc, close to the Hipparcos value o f 75+/-6 pc.