We present a study of seven southern open clusters based on UBVRI CCD photometry (Johnsons-Cousins system) and Gaia DR2 data. Dias4, Dias6, and four other clusters had UBVRI photometric observations determined for the first time. From the observational UBVRI data we obtained photometric membership probability estimates and, using the proper motions from the UCAC5 catalogue, we also determined the kinematic membership. From Gaia DR2 astrometric data we determine the stellar membership using proper motions and parallaxes, taking into account the full covariance matrix. For both independent sets of data and membership we apply our non-subjective multidimensional global optimization tool to fit theoretical isochrones to determine the distance, age, reddening, metallicity, and binary fraction of the clusters. The results of the mean proper motions, distances, and ages are in agreement, but the ones obtained from Gaia DR2 data are more precise in both membership selection and estimated parameters. In the case of NGC 6087, the Cepheid S Nor, member of the open cluster, was used to obtain an independent distance estimate, confirming the one determined by our fitting method. We also report a serendipitous discovery of two new clusters in the extended field near what was originally Dias4.
Cone search capability for table J/MNRAS/481/3887/c307g (Collinder 307 Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/d4ag2 (Dias 4a Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/d4bg2 (Dias 4b Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/d6g (Dias 6 Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/ic4651g (IC 4651 Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/ngc5138g (NGC 5138 Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/ngc6087g (NGC 6087 Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/ngc6178g (NGC 6178 Gaia DR2 Data)
Cone search capability for table J/MNRAS/481/3887/c307p (Collinder 307 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/d4p (Dias 4 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/d6p (Dias 6 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/ic4651p (IC 4651 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/ngc5138p (NGC 5138 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/ngc6087p (NGC 6087 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/ngc6178p (NGC 6178 UBVRI and JHKs Data with photometric membership)
Cone search capability for table J/MNRAS/481/3887/c307k (Collinder 307 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
Cone search capability for table J/MNRAS/481/3887/d4k (Dias 4 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
Cone search capability for table J/MNRAS/481/3887/d6k (Dias 6 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
Cone search capability for table J/MNRAS/481/3887/ic4651k (IC 4651 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
Cone search capability for table J/MNRAS/481/3887/ngc5138k (NGC 5138 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
Cone search capability for table J/MNRAS/481/3887/ngc6087k (NGC 6078 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
Cone search capability for table J/MNRAS/481/3887/ngc6178k (NGC 6178 UBVRI and JHKs Data with the computed mean of photometric and kinematic memberships)
