Antichi, Jacopo, Dohlen, Kjetil, Gratton, Raffaele G., Mesa, Dino, Claudi, Riccardo U., Giro, Enrico, ...
Integral field spectroscopy (IFS) represents a powerful technique for the detection and characterization of extrasolar planets through high contrast imaging, since it allows to obtain simultaneously...
Properties of second generation stars in Globular Clusters (2008)
Carretta, Eugenio, Bragaglia, Angela, Gratton, Raffaele G., Lucatello, Sara
We present the first results from the analysis of GIRAFFE spectra of more than 1200 red giants stars in 19 Galactic Globular Clusters (GCs), to study the chemical composition of second generation...
EPICS: the exoplanet imager for the E-ELT (2008)
Kasper, Markus E., Beuzit, Jean-Luc, Verinaud, Christophe, Yaitskova, Natalia, Baudoz, Pierre, Boccaletti, Anthony, ...
Presently, dedicated instrument developments at large telescopes (SPHERE for the VLT, GPI for Gemini) are about to discover and explore self-luminous giant planets by direct imaging and spectroscopy....
Carretta, Eugenio, Recio-Blanco, Alejandra, Gratton, Raffaele G., Piotto, Giampaolo, Bragaglia, Angela
We find a strong correlation between the extension of the Na-O anticorrelation observed in red giant branch (RGB) stars and the high temperature extension of the horizontal branch (HB) blue tails of...
Variations in the lithium abundances of turn off stars in the globular cluster 47 Tuc (2007)
Bonifacio, Piercarlo, Pasquini, Luca, Molaro, Paolo, Carretta, Eugenio, François, Patrick, Gratton, Raffaele G., ...
aims: Our aim is to determine Li abundances in TO stars of the Globular Cluster 47 Tuc and test theories about Li variations among TO stars. method: We make use of high resolution (R~ 43000), high...
Beryllium abundance in turn-off stars of NGC 6752 (2006)
Pasquini, Luca, Bonifacio, Piercarlo, Randich, Sofia, Galli, Daniele, Gratton, Raffaele G., Wolff, B.
Aims: To measure the beryllium abundance in two TO stars of the Globular Cluster NGC 6752, one oxygen rich and sodium poor, the other presumably oxygen poor and sodium rich. Be abundances in these...
A simulation code for AO assisted 3D spectroscopic imaging of extrasolar planets (2006)
Berton, Alessandro, Feldt, Markus, Gratton, Raffaele G., Henning, Thomas, Desidera, Silvano, Hippler, Stefan, ...
The Binary Frequency Among Carbon-Enhanced, s-Process Rich, Metal-Poor Stars (2004)
Lucatello, Sara, Tsangarides, Stelios, Beers, Timothy C., Carretta, Eugenio, Gratton, Raffaele G., Ryan, Sean G.
We discuss radial velocities for a sample of carbon-enhanced, s-process rich, very metal-poor stars (CEMP-s hereafter), analyzed with high-resolution spectroscopy obtained over multiple epochs. We...
Observational evidence for a different IMF in the early Galaxy (2004)
Lucatello, Sara, Gratton, Raffaele G., Beers, Timothy C., Carretta, Eugenio
The unexpected high incidence of carbon-enhanced, s-process enriched unevolved stars amongst extremely metal-poor stars in the halo provides a significant constraint on the Initial Mass Function...
Simulations versus observations obtained with simultaneous differential imaging (2004)
Berton, Alessandro, Kellner, Stefan, Feldt, Markus, Masciadri, Elena, Lenzen, Rainer, Brandner, Wolfgang, ...
Simulations of exoplanets detection obtained with a high-contrast imaging instrument: CHEOPS (2004)
Berton, Alessandro, Gratton, Raffaele G., Feldt, Markus, Desidera, Silvano, Masciadri, Elena, Turatto, Massimo, ...
Carretta, Eugenio, Cohen, Judith G., Gratton, Raffaele G., Behr, Bradford B.
We present the results of the first analysis of high dispersion spectra of four red HB stars in the metal rich globular cluster NGC 6528, located in Baade's Window. We find that the mean [Fe/H] for...
Cohen, Judith G., Gratton, Raffaele G., Behr, Bradford B., Carretta, Eugenio
We provide a high dispersion line-by-line abundance analysis of five red HB stars in the extremely metal rich galactic globular cluster NGC 6553. These red HB stars are significantly hotter than the...
Carretta, Eugenio, Gratton, Raffaele G., Clementini, Gisella, Pecci, Flavio Fusi
We discuss the different biases affecting the sample of field subdwarfs selected from the Hipparcos Catalogue, and used in the Main Sequence Fitting technique to derive distances to Galactic Globular...
The absolute magnitude of field metal-poor horizontal branch stars (1997)
HIPPARCOS satellite parallaxes for 22 metal-poor field horizontal branch stars with Vo