794 citations · 10.8k across the 137 of their papers we have counts for
8 papers · 1 filter
An aluminium tool for multiple stellar generations in the globular clusters 47 Tuc and M 4
Eugenio Carretta, Raffaele Gratton, Angela Bragaglia +2
We present aluminium abundances for a sample of about 100 red giant stars in each of the Galactic globular clusters 47 Tuc (NGC 104) and M 4 (NGC 6121). We have derived homogeneous…
Fluorine variations in the globular cluster NGC 6656 (M22): implications for internal enrichment timescales
Valentina D'Orazi, Sara Lucatello, Maria Lugaro +8
Observed chemical (anti)correlations in proton-capture elements among globular cluster stars are presently recognized as the signature of self-enrichment from now extinct, previous…
Searching for multiple stellar populations in the massive, old open cluster Berkeley 39
A. Bragaglia, R. G. Gratton, E. Carretta +3
The most massive star clusters include several generations of stars with a different chemical composition (mainly revealed by an Na-O anti-correlation) while low-mass star clusters…
Spectroscopic hint of a cold stream in the direction of the globular cluster NGC 1851
A. Sollima, R. G. Gratton, J. A. Carballo-Bello +5
We present the results of a spectroscopic survey performed in the outskirts of the globular cluster NGC1851 with VIMOS@VLT. The radial velocities of 107 stars in a region between 1…
Spectroscopic analysis of the two subgiant branches of the globular cluster NGC1851
R. G. Gratton, S. Villanova, S. Lucatello +5
NGC1851 possibly shows a spread in [Fe/H], but the relation between this spread and the division in the SGB is unknown. We obtained blue (3950-4600 A) intermediate resolution (R~8,…
C, N, O abundances and carbon isotope ratios in evolved stars of the open clusters Collinder 261 and NGC 6253
Šarūnas Mikolaitis, Gražina Tautvaišienė, Raffaele Gratton +2
Context. Investigations of abundances of carbon and nitrogen in the atmospheres of evolved stars of open clusters may provide comprehensive information on chemical composition chan…