Search Publications
Planet or brown dwarf? Inferring the companion mass in HD 100546 from the wall shape using mid-infrared interferometry
van Boekel, Roy; Panić, Olja; Mulders, Gijs D. +3 more
Context. Giant planets form in protoplanetary disks while these disks are still gas-rich, and can reveal their presence through the annular gaps they carve out. HD 100546 is a gas-rich disk with a wide gap between a radius of ~1 and 13 AU, possibly cleared out by a planetary companion or planetary system.
Aims: We aim to identify the nature o…
Observationally driven 3D magnetohydrodynamics model of the solar corona above an active region
Peter, H.; Bingert, S.; Bourdin, Ph. -A.
Context.
Aims: The goal is to employ a 3D magnetohydrodynamics (MHD) model including spectral synthesis to model the corona in an observed solar active region. This will allow us to judge the merits of the coronal heating mechanism built into the 3D model.
Methods: Photospheric observations of the magnetic field and horizontal velocities…
An in-depth study of HD 174966 with CoRoT photometry and HARPS spectroscopy. Large separation as a new observable for δ Scuti stars
Auvergne, M.; Amado, P. J.; Baudin, F. +18 more
Aims: The aim of this work was to use a multi-approach technique to derive the most accurate values possible of the physical parameters of the δ Sct star HD 174966, which was observed with the CoRoT satellite. In addition, we searched for a periodic pattern in the frequency spectra with the goal of using it to determine the mean density of th…
The degeneracy between dust colour temperature and spectral index. Comparison of methods for estimating the β(T) relation
Juvela, M.; Ysard, N.; Montillaud, J. +1 more
Context. Submillimetre dust emission provides information on the physics of interstellar clouds and dust. However, noise can produce a spurious anticorrelation between the colour temperature TC and the spectral index β. These artefacts must be separated from the intrinsic β(T) relation of dust emission.
Aims: We compare methods tha…
Herschel far-infrared observations of the Carina Nebula complex. III. Detailed cloud structure and feedback effects
Preibisch, T.; Roccatagliata, V.; Gaczkowski, B. +1 more
Context. The star formation process in large clusters/associations can be strongly influenced by the feedback from high-mass stars. Whether the resulting net effect of the feedback is predominantly negative (cloud dispersal) or positive (triggering of star formation due to cloud compression) is still an open question.
Aims: The Carina Nebula …
Physical properties of high-mass clumps in different stages of evolution
Molinari, S.; Giannetti, A.; Beltrán, M. T. +6 more
Context. The details of the process of massive star formation are still elusive. A complete characterization of the first stages of the process from an observational point of view is needed to constrain theories on the subject. In the past 20 years we have made a thorough investigation of colour-selected IRAS sources over the whole sky. The source…
NGC 6240 : extended CO structures and their association with shocked gas
Aussel, H.; Elbaz, D.; Le Floc'h, E. +7 more
We present deep CO(1-0) observations of
Accuracy of magnetic energy computations
Démoulin, P.; Masson, S.; Pariat, E. +1 more
Context. For magnetically driven events, the magnetic energy of the system is the prime energy reservoir that fuels the dynamical evolution. In the solar context, the free energy (i.e., the energy in excess of the potential field energy) is one of the main indicators used in space weather forecasts to predict the eruptivity of active regions. A tr…
Large scale IRAM 30 m CO-observations in the giant molecular cloud complex W43
Hill, T.; Schneider, N.; Ossenkopf, V. +11 more
We aim to fully describe the distribution and location of dense molecular clouds in the giant molecular cloud complex W43. It was previously identified as one of the most massive star-forming regions in our Galaxy. To trace the moderately dense molecular clouds in the W43 region, we initiated W43-HERO, a large program using the IRAM 30 m telescope…
Obscuration effects in super-soft-source X-ray spectra
Behar, E.; Ness, J. -U.; Henze, M. +11 more
Context. Super-soft-source (SSS) X-ray spectra are blackbody-like spectra with effective temperatures ~3-7 × 105 K and luminosities of 1035-38 erg s-1. Grating spectra of SSS and novae in outburst that show SSS type spectra display atmospheric absorption lines. Radiation transport atmosphere models can be used to d…