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We report on the results of an extensive Very Large Telescope high-resolution imaging campaign of the central region of the giant globular cluster ω Centauri. More than 100000 stars have been measured in the inner 9 x 9 arcmin 2 region of the cluster. On the basis of multiband colour-magnitude diagrams, we confirm the existence of multiple stellar populations along the red giant branch (RGB). Moreover, thanks to the high precision of this data set, we conclude that the RGB does not present a smooth and continuous distribution, but shows a discrete structure: besides the metal-poor and the extreme metal-rich population (anomalous RGB), the existence of three metal intermediate populations is shown.

We present wide field (33 X 34 arcmin^2) multiband (BVI) CCD photometry (down to I, Comment: accepted by MNRAS Letters - 6 pages, 4 .eps figures. Standard LaTeX, mn.sty

The globular cluster M2 has a photometrically detected double red giant branch (RGB) sequence. We investigate here the chemical differences between the two RGBs in order to gain insight in the star formation history of this cluster. The low-resolution spectra, covering the blue spectral range, were collected with the Multi-Object Double CCD Spectrograph (MODS) on the Large Binocular Telescope, and analysed via spectrum synthesis technique. The high quality of the spectra allows us to measure C, N, Ba and Sr abundances relative to iron for 15 RGB stars distributed along the two sequences. We add to the MODS sample C and N measurements for 35 additional stars belonging to the blue RGB sequence, presented in Lardo et al. We find a clear separation between the two groups of stars in s-process elements as well as C and N content. Both groups display a C-N anticorrelation and the red RGB stars are on average richer in C and N with respect to the blue RGB. Our results reinforce the suggestion that M2 belongs to the family of globular clusters with complex star formation history, together with ω Cen, NGC 1851 and M22.

We present accurate wide-field uVI photometry of the remote and massive Galactic globular cluster NGC 2419, aimed at searching for the u-V color spread along the Red Giant Branch (RGB) that is generally interpreted as the photometric signature of the presence of multiple populations in globular clusters. Focusing on the RGB stars in the magnitude range 19.80.0 lie preferentially on the blue side., Comment: 13 pages, 12 figure, accepted for publication on MNRAS