691 citations · 22.3k across the 346 of their papers we have counts for
4 papers · 1 filter
The anomalous Galactic globular cluster NGC 2808
L. R. Bedin, G. Piotto, M. Zoccali +4
We present UBVI photometry for about 60,000 stars in a region of 44'x33' centered on the Galactic globular cluster (GGC) NGC 2808. The central region has been mapped with the HST W…
Comparison between Observed and Theoretical Red Giant Branch Luminosity Functions of Galactic Globular Clusters
M. Zoccali, G. Piotto
V-band luminosity functions have been obtained for the upper main-sequence, sub-giant branch and red giant branch of 18 galactic globular clusters from HST data. A comparison with…
New evidence for the complex struscture of the RGB of Omega Cen
E. Pancino, F. R. Ferraro, M. Bellazzini +2
We report on the complex structure of the red giant branch (RGB) of omega Cen, based on a new wide field and wide color baseline B and I photometry. Our color magnitude diagram (CM…
On the helium content of Galactic globular clusters via the R parameter
M. Zoccali, S. Cassisi, G. Bono +3
We estimate the empirical R parameter in 26 Galactic Globular Clusters covering a wide metallicity range, imaged by WFPC2 on board the HST. The improved spatial resolution permits…