Search Publications
The mean star-forming properties of QSO host galaxies
Berta, S.; Magnelli, B.; Nordon, R. +22 more
Quasi-stellar objects (QSOs) occur in galaxies in which supermassive black holes (SMBHs) are growing substantially through rapid accretion of gas. Many popular models of the co-evolutionary growth of galaxies and black holes predict that QSOs are also sites of substantial recent star formation (SF), mediated by important processes, such as major m…
Macroclumping as solution of the discrepancy between Hα and P v mass loss diagnostics for O-type stars
Hamann, W. -R.; Oskinova, L. M.; Aret, A. +3 more
Context. Recent studies of O-type stars have demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed. Fitting the unsaturated UV resonance lines (e.g., P v) gives drastically lower values than obtained from the Hα emission. Wind inhomogeneity (so-called "clumping") may be the main cause of this disc…
Improved photometric calibration of the SNLS and the SDSS supernova surveys
Kessler, R.; Marriner, J.; Sako, M. +13 more
Context. We present a combined photometric calibration of the Supernova Legacy Survey (SNLS) and the SDSS supernova survey, which results from a joint effort of the SDSS and the SNLS collaborations.
Aims: Our primary motivation is to eventually sharpen cosmological constraints derived from type Ia supernova measurements by improving the accur…
Hubble Space Telescope detection of oxygen in the atmosphere of exoplanet HD 189733b
Ballester, G. E.; Ben-Jaffel, L.
Detecting heavy atoms in the inflated atmospheres of giant exoplanets that orbit close to their parent stars is a key factor for understanding their bulk composition, their evolution, and the processes that drive their expansion and interaction with the impinging stellar wind. Unfortunately, very few detections have been made thus far. Here, we us…
Planck intermediate results. VIII. Filaments between interacting clusters
Böhringer, H.; Kneissl, R.; Bernard, J. -P. +205 more
Context. About half of the baryons of the Universe are expected to be in the form of filaments of hot and low-density intergalactic medium. Most of these baryons remain undetected even by the most advanced X-ray observatories, which are limited in sensitivity to the diffuse low-density medium.
Aims: The Planck satellite has provided hundreds …
GMASS ultradeep spectroscopy of galaxies at z ~ 2. VII. Sample selection and spectroscopy
Berta, S.; Cimatti, A.; Daddi, E. +12 more
Context. Ultra-deep imaging of small parts of the sky has revealed many populations of distant galaxies, providing insight into the early stages of galaxy evolution. Spectroscopic follow-up has mostly targeted galaxies with strong emission lines at z > 2 or concentrated on galaxies at z < 1.
Aims: The populations of both quiescent and a…
Vindicating single-T modified blackbody fits to Herschel SEDs
Bianchi, S.
I show here that the bulk of the dust mass in a galaxy can be equivalently estimated from i) the full spectral energy distribution of dust emission, using the approach of Draine & Li (2007, ApJ, 657, 810) that includes a distribution of dust grains and a range of interstellar radiation field intensities; ii) the emission in the wavelength rang…
Excited OH+, H2O+, and H3O+ in NGC 4418 and Arp 220
Lutz, D.; Genzel, R.; Poglitsch, A. +15 more
We report on Herschel/PACS observations of absorption lines of OH+, H2O+ and H3O+ in NGC 4418 and Arp 220. Excited lines of OH+ and H2O+ with Elower of at least 285 and ~200 K, respectively, are detected in both sources, indicating radiative pumping …
DIGIT survey of far-infrared lines from protoplanetary disks. I. [O i], [C ii], OH, H2O, and CH+
Güdel, M.; Fedele, D.; Henning, Th. +10 more
We present far-infrared (50-200 µm) spectroscopic observations of young pre-main-sequence stars taken with Herschel/PACS as part of the DIGIT key project. The sample includes 16 Herbig AeBe and 4 T Tauri sources observed in SED mode covering the entire spectral range. An additional 6 Herbig AeBe and 4 T Tauri systems have been observed in SE…
A survey of young, nearby, and dusty stars conducted to understand the formation of wide-orbit giant planets. VLT/NaCo adaptive optics thermal and angular differential imaging
Lagrange, A. -M.; Desidera, S.; Bonnefoy, M. +7 more
Context. Over the past decade, direct imaging has confirmed the existence of substellar companions on wide orbits from their parent stars. To understand the formation and evolution mechanisms of these companions, their individual as well as the full population properties must be characterized.
Aims: We aim at detecting giant planet and/or bro…