Integrated luminosity distribution of Galactic open clusters

The integrated magnitudes of 221 Galactic open clusters have been used to derive the luminosity function. The completeness of the data has also been discussed. In the luminosity distribution the maximum frequency of clusters occurs nearI (M_v) = −3 _m ^. 5, and some plausible reasons for a sharp cut-off atI (M_v) = −2^m. 0 have been discussed. It is concluded that the paucity of the clusters fainter thanI (M _v) = −2 _m ^.0 is not purely due to selection effects. The surface density of the clusters for different magnitude intervals has. been obtained using the completeness radius estimated from the logN- logd plots. A relation betweenI (M^v) and surface density has been obtained which yields a steeper slope than that obtained by van den Bergh & Lafontaine (1984).