A dedicated photometric system for the classification of Wolf-Rayet stars^*

Institut d'Astrophysique, Université de Liège, 5, avenue de Cointe, B-4000 Liège, Belgium

Send offprint request to: P. Royer

Received: 20 October 1997
Accepted: 17 December 1997

Abstract

We present here tests of a five-filter photometric system aimed at WR classification. In addition to the well-known easy separation between the WN and WC spectral types, these tests indicate interesting potentialities in the discrimination of subgroups among the WN and the WC which look well related to the classical subtypes. The proposed combinations of filters (or derived ones) bear enough discriminating power to satisfy some evolutionary studies in crowded fields where spectroscopic follow-up is not possible.