Search Publications
Lithium abundances of halo dwarfs based on excitation temperature. I. Local thermodynamic equilibrium
García Pérez, A. E.; Norris, J. E.; Ryan, S. G. +2 more
Context: The discovery of the Spite plateau in the abundances of 7Li for metal-poor stars led to the determination of an observationally deduced primordial lithium abundance. However, after the success of the Wilkinson Microwave Anisotropy Probe (WMAP) in determining the baryon density, Ω_Bh2, there was a discrepancy between …
Designing future dark energy space missions. I. Building realistic galaxy spectro-photometric catalogs and their first applications
Kneib, J. -P.; Aussel, H.; Ilbert, O. +12 more
Context: Future dark energy space missions such as JDEM and EUCLID are being designed to survey the galaxy population to trace the geometry of the universe and the growth of structure, which both depend on the cosmological model. To reach the goal of high precision cosmology they need to evaluate the capabilities of different instrument designs ba…
The physical properties of Lyα emitting galaxies: not just primeval galaxies?
Castellano, M.; Pentericci, L.; Santini, P. +4 more
Aims: We have analyzed a sample of Lyman break galaxies from z ~ 3.5 to z ~ 6 selected from the GOODS-S field as B, V, and i-dropouts, and with spectroscopic observations showing that they have the Lyα line in emission. Our main aim is to investigate their physical properties and their dependence on the emission line characteristic and to shed lig…
The radial distribution of the two stellar populations in NGC 1851
Salaris, M.; Anderson, J.; Milone, A. P. +4 more
We have analyzed ACS/WFC and WFPC2 images from HST, as well as ground-based data to study the radial distribution of the double sub-giant branch (SGB) recently discovered in the Galactic globular cluster NGC 1851. We found that the SGB split can be followed all the way from the cluster center out to at least 8´ from the center. Beyond this distanc…
Unveiling the nature of INTEGRAL objects through optical spectroscopy. VII. Identification of 20 Galactic and extragalactic hard X-ray sources
Palazzi, E.; Minniti, D.; Masetti, N. +17 more
Within the framework of our program of assessment of the nature of unidentified or poorly known INTEGRAL sources, we present here spectroscopy of optical objects, selected through positional cross-correlation with soft X-ray detections (afforded with satellites such as Swift, ROSAT, Chandra and/or XMM-Newton) as putative counterparts of hard X-ray…
A possible architecture of the planetary system HR 8799
Krivov, A. V.; Löhne, T.; Neuhäuser, R. +4 more
HR 8799 is a nearby A-type star with a debris disk and three planetary candidates, which have been imaged directly. We undertake a coherent analysis of various observational data for all known components of the system, including the central star, imaged companions, and dust. Our goal is to elucidate the architecture and evolutionary status of the …
VLT-FLAMES analysis of 8 giants in the bulge metal-poor globular cluster NGC 6522: oldest cluster in the Galaxy?. Analysis of 8 giants in NGC 6522
Minniti, D.; Zoccali, M.; Bica, E. +5 more
Context: NGC 6522 has been the first metal-poor globular cluster identified in the bulge by Baade. Despite its importance, very few high-resolution abundance analyses of stars in this cluster are available. The bulge metal-poor clusters may be important tracers of the early chemical enrichment of the Galaxy.
Aims: The main purpose of this stud…
Revealing X-ray obscured quasars in SWIRE sources with extreme mid-IR/optical flux ratios
Salvato, M.; Fiore, F.; Vignali, C. +4 more
Recent works have suggested that selection criteria based on mid-IR properties, i.e. extreme colors and bright flux levels, can be used to reveal a population of dust-enshrouded, extremely-luminous quasars at z ∼ 1-2. However, the X-ray spectral properties of these intriguing objects still remain largely unexplored. We have performed an X-ray stud…
Small-scale oscillations in a quiescent prominence observed by HINODE/SOT. Prominence oscillations
Ichimoto, K.; Cao, W.; Qu, Z. Q. +2 more
Context: Investigations of the behavior of small-scale threads can provide an alternative approach to studying prominence dynamics and understanding its origin and nature.
Aims: The behavior of threads are analyzed in a quiescent prominence, including drifting and both the horizontally and vertically oscillating motions. These indicate waves i…
Photometric mass and mass decomposition in early-type lens galaxies
Grillo, C.; Rosati, P.; Lombardi, M. +1 more
Context: The largest spectroscopically selected sample of strong gravitational lens systems presented and analyzed to date is that of the Sloan Lens ACS (SLACS) survey. For the 57 massive early-type lens galaxies in the sample, photometric and spectroscopic measurements are available from the Sloan Digital Sky Survey (SDSS).
Aims: By using the…