Search Publications
Accurate fundamental parameters of CoRoT asteroseismic targets. The solar-like stars HD 49933, HD 175726, HD 181420, and HD 181906
Bruntt, H.
Context: The CoRoT satellite has provided high-quality light curves of several solar-like stars. Analysis of these light curves provides oscillation frequencies that make it possible to probe the interior of the stars. However, additional constraints on the fundamental parameters of the stars are important for the theoretical modelling to be succe…
A candidate tidal disruption event in the Galaxy cluster Abell 3571
Greiner, J.; Esquej, P.; Salvato, M. +8 more
Context: Tidal disruption events are possible sources of temporary nuclear activity in galactic nuclei and can be considered as good indicators of the existence of supermassive black holes in the centers of galaxies.
Aims: A new X-ray source has been detected serendipitously with ROSAT in a PSPC pointed observation of the galaxy cluster A3571.…
The detached haze layer in Titan's mesosphere
Lavvas, Panayotis; Yelle, Roger V.; Vuitton, Véronique
By comparing observations from the Cassini imaging system, UV spectrometer, and Huygens atmospheric structure instrument, we determine an apparent radius of ∼40 nm, an imaginary index <0.3 at 187.5 nm and a number density of ∼30 particles cm -3 for the detached haze layer at 520 km in Titan's mesosphere. We point out that the detache…
The stellar association around Gamma Velorum and its relationship with Vela OB2
Naylor, Tim; Jeffries, R. D.; Walter, F. M. +2 more
We present the results of a photometric BVI survey of 0.9deg2 around the Wolf-Rayet binary γ2 Vel and its early-type common proper motion companion γ1 Vel (together referred to as the γ Vel system). Several hundred pre-main-sequence (PMS) stars are identified and the youth of a subset of these is spectroscopically …
The size distribution of magnetic bright points derived from Hinode/SOT observations
Möstl, C.; Veronig, A.; Utz, D. +3 more
Context: Magnetic bright points (MBPs) are small-scale magnetic features in the solar photosphere. They may be a possible source of coronal heating by rapid footpoint motions that cause magnetohydrodynamical waves. The number and size distribution are of vital importance in estimating the small scale-magnetic-field energy.
Aims: The size distr…
Resolved 24.5 micron emission from massive young stellar objects
Onaka, T.; Kataza, H.; Hoare, M. G. +8 more
Context: Massive young stellar objects (MYSO) are surrounded by massive dusty envelopes, whose physical structure and geometry are determined by the star formation process.
Aims: Our principal aim is to establish the density structure of MYSO envelopes on scales of ~1000 AU. This constitutes an increase of a factor ~10 in angular resolution co…
A New View of Coronal Waves from STEREO
Golub, L.; Chen, P. F.; Lin, J. +6 more
On 2007 December 7, there was an eruption from AR 10977, which also hosted a sigmoid. An EUV Imaging Telescope (EIT) wave associated with this eruption was observed by EUVI on board the Solar Terrestrial Relations Observatory (STEREO). Using EUVI images in the 171 Å and the 195 Å passbands from both STEREO A and B, we study the morphology and kine…
CAIXA: a catalogue of AGN in the XMM-Newton archive. II. Multiwavelength correlations
Bianchi, S.; Ponti, G.; Guainazzi, M. +2 more
Aims: The availability of large amounts of multiwavelength data allows us to perform an extensive statistical analysis to look for correlations between different parameters of AGN. The physical implications of these correlations, when considered within the framework of current AGN models, can be enlightening in the resolution of the problems and t…
INTEGRAL/IBIS and Swift/XRT observations of hard cataclysmic variables
Bird, A. J.; Fiocchi, M.; Landi, R. +5 more
The analysis of the third INTEGRAL/Imager on Board Integral Satellite (IBIS) survey has revealed several new cataclysmic variables, most of which turned out to be intermediate polars, thus confirming that these objects are strong emitters in hard X-rays. Here, we present high-energy spectra of all 22 cataclysmic variables detected in the third IBI…
Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole
Golub, Leon; van Ballegooijen, Adriaan; Schmieder, Brigitte +4 more
A B1.7 two-ribbon flare occurred in a highly non-potential decaying active region near a coronal hole at 10:00 UT on 2008 May 17. This flare is "large" in the sense that it involves the entire region, and it is associated with both a filament eruption and a coronal mass ejection. We present multi-wavelength observations from EUV (TRACE, STEREO/EUV…