Tidal dwarf candidates in a sample of interacting galaxies

We present deep optical B,V,R images of a sample of 10 interacting systems which were selected for their resemblance to disturbed galaxies at high red shift. Photometry is performed on knots in the tidal features of the galaxi es. We calculate a grid of evolutionary synthesis models with two metallici ties and various burst strengths for systems consisting of some fraction of the stellar population of a progenitor spiral plus starburst. By compariso n with two-color diagrams we interpret the photometric data, select from a total of about 100 condensations 36 star-forming objects that ale located i n the tidal features and predict their further evolution. Being more lumino us by 4 mag than normal HII regions we argue that these objects could be ti dal dw,uf galaxies or their progenitors, although they differ in number and mean luminosity from the already known tidal dwarf galaxies typically loca ted at the end of tidal tails in nearby giant interacting systems. From com parison with our models we note that all objects show young burst ages. The young stellar component formed in these tidal dwarf candidates contributes up to 18% to the total stellar mass at the end of the starburst and domina tes the optical luminosity. This may result in fading by up to 2.5 mag in B during the next 200 Myrs after the burst.