Search Publications
Origin of wide-band IP type II bursts
Valtonen, E.; Allawi, H.; Pohjolainen, S.
Context. Different types of interplanetary (IP) type II bursts have been observed, where the more usual ones show narrow-band and patchy emissions, sometimes with harmonics, and which at intervals may disappear completely from the dynamic spectrum. The more unusual bursts are wide-band and diffuse, show no patches or breaks or harmonic emission, a…
Regular frequency patterns in the young δ Scuti star HD 261711 observed by the CoRoT and MOST satellites
Auvergne, M.; Chaintreuil, S.; Ryabchikova, T. +14 more
Context. The internal structure of pre-main-sequence (PMS) stars is poorly constrained at present. This could change significantly through high-quality asteroseismological observations of a sample of such stars.
Aims: We concentrate on an asteroseismological study of HD 261711, a rather hot δ Scuti-type pulsating member of the young open clus…
Is the bowshock of the runaway massive star HD 195592 a Fermi source?
De Becker, M.; Romero, G. E.; del Valle, M. V.
Context. HD 195592 is an O-type super-giant star, known as a well-established runaway. Recently, a Fermi γ-ray source (2FGL J2030.7+4417) with a position compatible with that of HD 195592 has been reported.
Aims: Our goal is to explore the scenario where HD 195592 is the counterpart of the Fermi γ-ray source, modeling the non-thermal emission…
Pushing the limits of the Gaia space mission by analyzing galaxy morphology
Ducourant, C.; Gavras, P.; Galluccio, L. +6 more
Context. The ESA Gaia mission, to be launched during 2013, will observe billions of objects, among which many galaxies, during its 5 yr scanning of the sky. This will provide a large space-based dataset with unprecedented spatial resolution.
Aims: Because of its natural Galactic and astrometric priority, Gaia's observational strategy was opti…
Amorphous carbon in the disk around the post-AGB binary HR 4049. Discerning dust species with featureless opacity curves
Verhoelst, T.; Acke, B.; Lombaert, R. +7 more
Context. Infrared spectroscopy has been extensively used to determine the mineralogy of circumstellar dust. The identification of dust species with featureless opacities, however, is still ambiguous. Here we present a method to lift the degeneracy using the combination of infrared spectroscopy and interferometry.
Aims: The binary post-AGB sta…
Multi-wavelength landscape of the young galaxy cluster RX J1257.2+4738 at z = 0.866. I. The infrared view
Altieri, B.; Cepa, J.; Valtchanov, I. +16 more
Context. Many studies have shown how galaxy properties (e.g. colours, morphology, star-forming (SF) activity, active galactic nuclei population) change not only with redshift, but also with local galaxy density, revealing the important effect of the stellar/halo mass and the environment in the evolution of galaxies. A detailed analysis of the star…
Warm gas in the rotating disk of the Red Rectangle: accurate models of molecular line emission
Alcolea, J.; Bujarrabal, V.
Aims: We aim to study the excitation conditions of the molecular gas in the rotating disk of the Red Rectangle, the only post-asymptotic-giant-branch object in which the existence of an equatorial rotating disk has been demonstrated. For this purpose, we developed a complex numerical code that accurately treats radiative transfer in 2D, adapt…
CoRoT 102749568: mode identification in a δ Scuti star based on regular spacings
Auvergne, M.; Guenther, E. W.; Gandolfi, D. +10 more
Context. The high accuracy of space data increased the number of the periodicities determined for pulsating variable stars, but the mode identification is still a critical point in the non-asymptotic regime.
Aims: We use regularities in frequency spacings for identifying the pulsation modes of the recently discovered δ Sct star ID 102749568. …
Physical properties of asteroid 308635 (2005 YU55) derived from multi-instrument infrared observations during a very close Earth approach
Altieri, B.; Metcalfe, L.; Pál, A. +19 more
The near-Earth asteroid 308635 (2005 YU55) is a potentially hazardous asteroid which was discovered in 2005 and passed Earth on Nov. 8, 2011 at 0.85 lunar distances. This was the closest known approach by an asteroid of several hundred metres in diameter since 1976 when an object of similar size passed at 0.5 lunar distances. We observe…
Simultaneous XMM-Newton and HST-COS observation of 1H0419-577. The absorbing and emitting ionized gas
Kaastra, J. S.; Arav, N.; Edmonds, D. +7 more
In this paper we analyze the X-ray, UV, and optical data of the Seyfert 1.5 galaxy 1H0419-577 with the aim of detecting and studying an ionized-gas outflow. The source was observed simultaneously in the X-rays with XMM-Newton and in the UV with HST-COS. Optical data were also acquired with the XMM-Newton Optical Monitor. We detected a thin, lowly …