Stars assoc. and open clusters subgroups

These findings motivated us to search for subgroups among the objects examined in our previous work, which employed fractal statistics. The present study considers seven open clusters that exhibit significant dispersion in age and/or proper motion distributions, suggesting that they are not single clusters.

In order to characterize the stellar groups, we calculate the membership probability using Bayesian multidimensional analysis by fitting the observed proper motion distribution of the candidates. A probability distribution is also used to determine the distance of the cluster, which is obtained from the mean value of the distance modes. The photometry from Gaia DR3 is compared with evolutionary models to estimate the cluster age and total mass.