THE SEARCH FOR DELTA-SCUTI STARS IN OPEN CLUSTERS

In order to improve the tests of models of stellar evolution, observat ions giving tighter constraints on the models were initiated by the fo rmation of an informal group STACC (Frandsen, 1992). The purpose of th e group is to search for and make observations of delta Scuti stars in open clusters. This paper presents some of the results of the search, mainly for distant open clusters with a rich population of variables. Included is an announcement of a target list (Frandsen & Arentoft 199 8, The Book) and four examples of new Colour-Magnitude (CM) diagrams o f open clusters considered to be interesting targets. Finally, we pres ent the fruits of extensive searching: an open cluster that contains m any delta Scuti stars.