The observed position of planetary nebulae nuclei on the luminosity - temperature diagram

The position of the central stars of planetary nebulae on the T/L diagram provides an important test of the stellar evolution theory. In this paper, we present, at first, a brief review of the recent works presented on this subject. The confrontation of observational results with theoretical models allows to precise the range of the masses of the central stars, which represents the main parameter governing their evolution. In the second part, we present the results of our new spectrophotometric survey; we have computed temperatures and luminosities of the central stars, using newly derived observational parameters and statistical distances. Taking into account the limitation both on our observations and on the used methods, the T/L diagram obtained enables us to estimate the range of the mass distribution