Search Publications
VLT/NACO coronagraphic observations of fine structures in the disk of β Pictoris
Augereau, J. -C.; Pantin, E.; Boccaletti, A. +2 more
Aims: We present ground-based observations of the disk around the A-type star β Pictoris to obtain scattered light images at the highest angular resolution (60 mas, equivalent to about 1 AU at the distance of the star) and the highest contrast in the very close environment of the star. The purpose of this program is to perform a close inspection o…
Mesoscale dynamics on the Sun's surface from HINODE observations
Roudier, Th.; Malherbe, J. M.; Meunier, N. +5 more
Context:
Aims: The interactions of velocity scales on the Sun's surface, from granulation to supergranulation are still not understood, nor are their interaction with magnetic fields. We thus aim at giving a better description of dynamics in the mesoscale range which lies between the two scales mentioned above.
Methods: We analyse a 48 h h…
Accurate classification of 17 AGNs detected with Swift/BAT
Palazzi, E.; Minniti, D.; Masetti, N. +16 more
Through an optical campaign performed at 5 telescopes located in the northern and the southern hemispheres, plus archival data from two on line sky surveys, we have obtained optical spectroscopy for 17 counterparts of suspected or poorly studied hard X-ray emitting active galactic nuclei (AGNs) detected with Swift/BAT in order to determine or bett…
A planet around the evolved intermediate-mass star HD 110014
Pasquini, L.; de Medeiros, J. R.; Hatzes, A. P. +5 more
Context: We found evidence for a sub-stellar companion around the K giant star HD 110014. This cool evolved star, with a spectral type K2III and an estimated mass between 1.9 and 2.4 M⊙, is slightly metal rich with [Fe/H] = 0.19 and a rotational velocity V sin i = 2.0 km s-1.
Aims: To search for extrasolar planets around …
XMM-Newton RGS spectrum of RX J0720.4-3125: an absorption feature at 0.57 keV
Haberl, F.; Neuhäuser, R.; Hohle, M. M. +2 more
Aims: By measuring the gravitational redshift of spectral features in the spectrum of thermal radiation emitted from neutron stars, useful constraints for the equation of state of superdense matter can be obtained via an estimate of the mass-to-radius ratio. We searched for spectral line features in the high-resolution X-ray spectrum of the isolat…
New visible spectra and mineralogical assessment of (21) Lutetia, a target of the Rosetta mission
Lazzarin, M.; Marchi, S.; Magrin, S. +1 more
The Rosetta spacecraft, launched on March 2nd 2004, in the course of its journey to the comet 67P/Churyumov-Gerasimenko (encounter foreseen in 2014), will fly past two asteroids: (2867) Steins and (21) Lutetia. On September 5th 2008 (2867) Steins was encountered. In this paper, we present two visible spectra of (21) Lutetia of different spectral r…
Origin of Lyα absorption in nearby starbursts and implications for other galaxies
Schaerer, D.; Kunth, D.; Atek, H.
Context: Despite the privileged position that Lyman-α (Lyα) emission line holds in the exploration of the distant universe and modern observational cosmology, the origin of the observed diversity of Lyα profiles still needs to be thoroughly explained. Observations of nearby star forming galaxies bring their batch of apparent contradictions between…
On the metal abundances inside mixed-morphology supernova remnants: the case of IC 443 and G166.0+4.3
Troja, E.; Miceli, M.; Bocchino, F.
Context: Recent developments in the study of mixed morphology supernova remnants (MMSNRs) have revealed the presence of metal-rich X-ray emitting plasma inside a fraction of these remnants, a feature not properly addressed by traditional models for these objects.
Aims: Radial profiles of thermodynamical and chemical parameters are needed for a…
X-ray optical depth diagnostics of T Tauri accretion shocks
Peres, G.; Sciortino, S.; Drake, J. J. +4 more
Context: In classical T Tauri stars, X-rays are produced by two plasma components: a hot low-density plasma, with frequent flaring activity, and a high-density lower temperature plasma. The former is coronal plasma related to the stellar magnetic activity. The latter component, never observed in non-accreting stars, could be plasma heated by the s…
Spectroscopic binaries among Hipparcos M giants. III. The eccentricity - period diagram and mass-transfer signatures
Jorissen, A.; Famaey, B.; Frankowski, A. +1 more
Context: This paper is the third one in a series devoted to studying the properties of binaries involving M giants.
Aims: We use a new set of orbits to construct the first (e - log P) diagram of an extensive sample of M giant binaries, to obtain their mass-function distribution, and to derive evolutionary constraints for this class of binaries…