Search Publications
A submillimetre search for cold extended debris disks in the β Pictoris moving group
Fridlund, M.; Olofsson, G.; Liseau, R. +4 more
Context: Previous observations with the Infrared Astronomical Satellite and the Infrared Space Observatory, and ongoing observations with Spitzer and AKARI, have led to the discovery of over 200 debris disks, based on detected mid- and far infrared excess emission, indicating warm circumstellar dust. To constrain the properties of these systems, e…
What can we learn about protoplanetary disks from analysis of mid-infrared carbonaceous dust emission?
Ménard, F.; Joblin, C.; Fuente, A. +1 more
Context: The disks of gas and dust that form around young stars and can lead to planet formation contain polycyclic aromatic hydrocarbons (PAHs) and very small grains (VSGs).
Aims: In this paper we analyze the mid-infrared (mid-IR) emission of these very small dust particles in a sample of 12 protoplanetary disks. Our goal is twofold: first we…
The first two transient supersoft X-ray sources in M 31 globular clusters and the connection to classical novae
Della Valle, M.; Stiele, H.; Pietsch, W. +12 more
Context: Classical novae (CNe) have been found to represent the major class of supersoft X-ray sources (SSSs) in our neighbour galaxy M 31.
Aims: We determine the properties and evolution of the two first SSSs ever discovered in the M 31 globular cluster (GC) system.
Methods: We have used XMM-Newton, Chandra and Swift observations of the c…
Signature of [SiPAH]+ π-complexes in the interstellar medium
Joblin, C.; Simon, A.; Joalland, B. +1 more
Aims: We investigate the presence of silicon atoms adsorbed on the surface of interstellar polycyclic aromatic hydrocarbons (PAHs) to form SiPAH π-complexes.
Methods: We used quantum chemistry calculations to obtain the structural, thermodynamic, and mid-IR properties of neutral and cationic SiPAH π-complexes.
Results: The binding energy w…
The origin of the supersoft X-ray-optical/UV flux anticorrelation in the symbiotic binary AG Draconis
González-Riestra, R.; Skopal, A.; Sekeráš, M. +1 more
Context: AG Draconis produces a strong supersoft X-ray emission. The X-ray and optical/UV fluxes are in strict anticorrelation throughout the active and quiescent phases.
Aims: We identify the source of the X-ray emission and reveal the nature of the observed flux anticorrelation.
Methods: We used X-ray and UV observations with XMM-Newton,…
Testing magnetically confined wind shock models for β Cephei using XMM-Newton and Chandra phase-resolved X-ray observations
Sanz-Forcada, J.; Neiner, C.; Favata, F. +2 more
Aims: We have performed a set of high- and low-spectral resolution phase-resolved X-ray observations of the magnetic B star β Cep, for which theoretical models predict the presence of a confined wind emitting X-rays from stationary shocks. Given the peculiar geometry of β Cep, some of the models predict strong rotational modulation of the X-ray em…
Stellar abundances and ages for metal-rich Milky Way globular clusters. Stellar parameters and elemental abundances for 9 HB stars in NGC 6352
Primas, F.; Feltzing, S.; Johnson, R. A.
Context: Metal-rich globular clusters provide important tracers of the formation of our Galaxy. Moreover, and not less important, they are very important calibrators for the derivation of properties of extra-galactic metal-rich stellar populations. Nonetheless, only a few of the metal-rich globular clusters in the Milky Way have been studied using…
Revealing the fastest component of the DG Tauri outflow through X-rays
Günther, H. M.; Matt, S. P.; Li, Z. -Y.
Context: Some T Tauri stars show a peculiar X-ray spectrum that can be modelled by two components with different absorbing column densities.
Aims: We seek to explain the soft X-ray component in DG Tau, the best studied of these sources, with an outflow model, taking observations at other wavelengths into consideration.
Methods: We constrai…
Swift follow-up observations of 17 INTEGRAL sources of uncertain or unknown nature
Chaty, S.; Tomsick, J. A.; Rodriguez, J.
Context: The positional accuracy of the IBIS telescope on-board INTEGRAL, albeit unprecedented in the >20 keV range, is still not good enough to identify many hard X-ray sources discovered by INTEGRAL. This indeed prevents counterparts from being found at other wavelengths, which is the only way to unveil the true nature of these sources.
A…
High energy variability of 3C 273 during the AGILE multiwavelength campaign of December 2007-January 2008
Caraveo, P. A.; Antonelli, L. A.; Costa, E. +52 more
Context: We report the results of a 3-week multi-wavelength campaign targeting the flat spectrum radio quasar 3C 273 carried out with the AGILE gamma-ray mission, covering the 30 MeV-50 GeV and 18-60 keV, the REM observatory (covering the near-IR and optical), Swift (near-UV/Optical, 0.2-10 keV and 15-50 keV), INTEGRAL (3-200 keV) and Rossi XTE (2…