SIMBAD references

Charge-coupled device (CCD) photometry in the Johnson V, Kron-Cousins I and Washington CMT₁systems is presented in the field of the poorly known open cluster NGC 2627. Four independent Washington abundance indices yield a mean cluster metallicity of [Fe/H]-0.12±0.08, which is compatible with the existence of a radial gradient in the Galactic disc. The resultant colour-magnitude diagrams indicate that the cluster is an intermediate-age object of 1.4 Gyr. Based on the best fits of the Geneva group's isochrones to the (V, V -I) and (T₁, C -T₁) diagrams, we estimate E (V -I) 0.25 ±0.05 and V -M_V11.80±0.25 for logt 9.15, and E (C -T₁) 0.23±0.07 and T₁-M_T111.85±0.25 for logt 9.10, respectively, assuming solar metal content. The derived reddening value E (C -T₁) implies E (B -V) 0.12±0.07 and a distance from the Sun of 2.0±0.4 kpc. Using the WEBDA data base and the available literature, we re-examined the overall properties of all the open clusters with ages between 0.6 and 2.5 Gyr. We identified peaks of cluster formation at 0.7-0.8, 1.0-1.1, 1.6-1.7 and 2.0-2.1 Gyr, separated by relative quiescent epochs of ∼0.2-0.3 Gyr. We also estimated a radial abundance gradient of -0.08±0.02, which is consistent with the most recent determinations for the Galactic disc, but no clear evidence for a gradient perpendicular to the Galactic plane is found.