Search Publications
The intensity contrast of solar granulation: comparing Hinode SP results with MHD simulations
Solanki, S. K.; Lagg, A.; Tsuneta, S. +5 more
Context: The contrast of granulation is an important quantity characterizing solar surface convection.
Aims: We compare the intensity contrast at 630 nm, observed using the Spectro-Polarimeter (SP) aboard the Hinode satellite, with the 3D radiative MHD simulations of Vögler & Schüssler (2007, A&A, 465, L43).
Methods: A synthetic im…
Unveiling the nature of INTEGRAL objects through optical spectroscopy. VI. A multi-observatory identification campaign
Palazzi, E.; Minniti, D.; Masetti, N. +18 more
Using 8 telescopes in the northern and southern hemispheres, plus archival data from two on-line sky surveys, we performed a systematic optical spectroscopic study of 39 putative counterparts of unidentified or poorly studied INTEGRAL sources in order to determine or at least better assess their nature. This was implemented within the framework of…
On the detectability of Lyα emission in star forming galaxies. The role of dust
Östlin, G.; Hayes, M.; Mas-Hesse, J. M. +2 more
Context: Lyman-alpha (Lyα) radiation is now widely used to investigate the galaxy formation and evolution in the high redshift universe. However, without a rigorous understanding of the processes regulating the Lyα escape fraction, physical interpretations of high-z observations remain questionable.
Aims: We examine six nearby star forming gal…
On the kinematic evolution of young local associations and the Scorpius-Centaurus complex
Figueras, F.; Torra, J.; Fernández, D.
Context: Over the last decade, several groups of young (mainly low-mass) stars have been discovered in the solar neighbourhood (closer than ~100 pc), thanks to cross-correlation between X-ray, optical spectroscopy and kinematic data. These young local associations - including an important fraction whose members are Hipparcos stars - offer insights…
Metal-rich multi-phase gas in M 87. AGN-driven metal transport, magnetic-field supported multi-temperature gas, and constraints on non-thermal emission observed with XMM-Newton
Finoguenov, A.; Böhringer, H.; Simionescu, A. +2 more
We use deep (~120 ks) XMM-Newton data of the M 87 halo to analyze its spatially resolved temperature structure and chemical composition. We focus particularly on the regions of enhanced X-ray brightness associated with the inner radio lobes, which are known not to be described very well by single-temperature spectral models. Compared to a simple t…
New observations of the extended hydrogen exosphere of the extrasolar planet HD 209458b
Ehrenreich, D.; Ferlet, R.; Vidal-Madjar, A. +6 more
Context: Atomic hydrogen escaping from the planet
TiO and VO broad band absorption features in the optical spectrum of the atmosphere of the hot-Jupiter HD 209458b
Ehrenreich, D.; Ferlet, R.; Vidal-Madjar, A. +4 more
Aims: The presence of titanium oxide (TiO) and vanadium oxide (VO) gas phase species is searched for in the atmosphere of the hot Jupiter
Methods: We compared a model for the planet's transmitted spectrum to multi-wavelength eclipse-depth measurements (from 3000 to 10 000 Å) using archived HST-STIS time series sp…
Strong lensing in Abell 1703: constraints on the slope of the inner dark matter distribution
Kneib, J. -P.; Pelló, R.; Egami, E. +9 more
Properties of dark matter haloes can be probed observationally and numerically, and comparing both approaches provides ways to constrain cosmological models. When it comes to the inner part of galaxy cluster scale haloes, interaction between the baryonic and the dark matter component is an important issue that is far from being fully understood. W…
IMAGES. I. Strong evolution of galaxy kinematics since z = 1
Cesarsky, C.; Östlin, G.; Yang, Y. +20 more
Nearly half the stellar mass of present-day spiral galaxies has formed since z = 1, and galaxy kinematics is an ideal tool to identify the underlying mechanisms responsible for the galaxy mass assembly since that epoch. Here, we present the first results of the ESO large program, “IMAGES”, which aims at obtaining robust measurements of the kinemat…
Pulsar timing for the Fermi gamma-ray space telescope
Camilo, F.; Dumora, D.; Guillemot, L. +25 more
We describe a comprehensive pulsar monitoring campaign for the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). The detection and study of pulsars in gamma rays give insights into the populations of neutron stars and supernova rates in the Galaxy, into particle acceleration mechanisms in neutron star magnetospher…