Near IR photometry of the old open clusters Berkeley 17 and Berkeley 18. Probing the age of the galactic disc

Giovanni Carraro, Antonella Vallenari, Leo Girardi +1

We report on near IR ($J$ and $K$ bands) observations of two $8\times 8\widetilde{(}arcmin{)}^2$ regions centered on the old open clusters Berkeley~17 and Berkeley~18, for which only optic…