Search Publications
The diverse X-ray properties of four truly isolated elliptical galaxies: NGC 2954, NGC 6172, NGC 7052, and NGC 7785
Wolter, A.; Trinchieri, G.; Memola, E. +2 more
Aims: We investigate the X-ray properties of four isolated elliptical galaxies, selected from the Updated Zwicky Catalog according to strict isolation criteria. Isolated galaxies are not influenced by the group/cluster environment, and their X-ray emission can be studied independently of the often overwhelming contribution of the hot intergalactic…
An HST/WFPC2 survey of bright young clusters in M31. I. VdB0, a massive star cluster seen at t ≃ 25 Myr
Barmby, P.; Bellazzini, M.; Galleti, S. +12 more
Aims: We introduce our imaging survey of possible young massive globular clusters in M31 performed with the Wide Field and Planetary Camera 2 (WFPC2) on the Hubble Space Telescope (HST). We obtained shallow (to B∼ 25) photometry of individual stars in 20 candidate clusters. We present here details of the data reduction pipeline that is being appli…
Planetary transit candidates in the CoRoT initial run: resolving their nature
Mazeh, T.; Aigrain, S.; Alonso, R. +45 more
With the release of CoRoT lightcurves of the Initial Run IRa01, 50 transiting planetary candidates have been published in a companion paper. About twenty of them were identified as binary stars from the CoRoT lightcurve itself. Complementary observations were conducted for 29 candidates, including ground-based photometry and radial-velocity measur…
The galactic unclassified B[e] star HD 50138. I. A possible new shell phase
Meilland, A.; Domiciano de Souza, A.; Chesneau, O. +4 more
Context: The observed spectral variation of HD 50138 has led different authors to classify it in a very wide range of spectral types and luminosity classes (from B5 to A0 and III to Ia) and at different evolutionary stages as either HAeBe star or classical Be.
Aims: Based on new high-resolution optical spectroscopic data from 1999 and 2007 ass…
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…