Open clusters are groups of coeval stars sharing properties such as distance and metallicity, and they are key to understanding stellar evolution. We shed light on the evolution of open clusters with a special focus on the universality of the luminosity function. We applied an upgraded version of the convergent point technique on about 50 open clusters. The selection of cluster members was based purely on the exquisite astrometry of the Gaia DR3 and HIPPARCOS catalogues in the five-dimensional or full six-dimensional space (when radial velocity is available). We present updated lists of bona fide members of about 50 open clusters within 500 pc and younger than 1 Gyr, exploiting the full depth of the third Gaia data release complemented by HIPPARCOS at the bright end, excluding regions in the Galactic plane. Our catalogues also are complemented by optical and infrared photometry from the major large-scale public surveys. All the data are available on a dedicated webpage with interactive plots and a direct link to Aladin and Vizier hosted at the Centre de Données de Strasbourg to facilitate its use from colleagues, amateur astronomers, and schools. We derived luminosity functions for all bound clusters and compared them in three age groups of approximately 50 Myr (reference is IC2602), 150 Myr (Pleiades-type), and 600 Myr (Hyades-type), discussing similarities and differences to constrain their dynamical evolution.

We conclude that the luminosity functions of clusters at 50 Myr are more likely similar to each other and show a greater degree of similarity than older clusters. We explain this observation with the universal luminosity function within the volume of our sample (500 pc). Luminosity functions of clusters with ages similar to the Pleiades or Hyades are more diverse, perhaps due to internal dynamical evolution, but more work is needed to provide additional evidence.

Webpage: http://research.iac.es/proyecto/gaiaclusters/about.php

References: Lodieu N., Smart R. L., Pérez-Garrido A., Silvotti, R. 2019, A&A, 623, 35: A 3D view of the Hyades stellar and sub-stellar population Lodieu N., Pérez-Garrido A., Smart R. L., Silvotti, R. 2019, A&A, 628, 66: A 5D view of the α Per, Pleiades, and Praesepe clusters Žerjal M., Lodieu N., Pérez-Garrido A., Olivares J., Bejar V. J. S., Martín E. L. 2023, A&A, 678, 75: Young nearby open clusters and their luminosity functions