Search Publications
Transmission spectrum of Venus as a transiting exoplanet
Tanga, P.; Ehrenreich, D.; Vidal-Madjar, A. +6 more
On 5-6 June 2012, Venus will be transiting the Sun for the last time before 2117. This event is an unique opportunity to assess the feasibility of the atmospheric characterisation of Earth-size exoplanets near the habitable zone with the transmission spectroscopy technique and provide an invaluable proxy for the atmosphere of such a planet. In thi…
An extension of the DUSTY radiative transfer code and an application to OH 26.5 and TT Cygni
Groenewegen, M. A. T.
For the best-studied nearby Galactic asymptotic giant branch (AGB) stars a wealth of observational data is typically available in the form of photometry, often extending into the sub-mm, spectra covering a wide wavelength range, and often also visibility curves. Almost 100 AGB stars and red super giants have been imaged as part of the MESS Hersche…
The nucleus of Comet 67P/Churyumov-Gerasimenko. A new shape model and thermophysical analysis
Lowry, S.; Snodgrass, C.; Green, S. F. +5 more
Context. Comet 67P/Churyumov-Gerasimenko is the target of the European Space Agency Rosetta spacecraft rendez-vous mission. Detailed physical characteristation of the comet before arrival is important for mission planning as well as providing a test bed for ground-based observing and data-analysis methods.
Aims: To conduct a long-term observa…
XMM-Newton observations of GX 13 + 1: correlation between photoionised absorption and broad line emission
Díaz Trigo, M.; Parmar, A. N.; Boirin, L. +1 more
We analysed data from five XMM-Newton observations of GX 13 + 1 to investigate the variability of the photo-ionised absorber in this source. We fitted EPIC and RGS spectra obtained from the "least-variable" intervals with a model consisting of disc-blackbody and blackbody components together with a Gaussian emission feature at ~6.55-6.7 keV modifi…
An independent distance estimate to CW Leonis
Blommaert, J. A. D. L.; Olofsson, G.; Gomez, H. L. +13 more
CW Leo has been observed six times between October 2009 and June 2012 with the SPIRE instrument on board the Herschel satellite. Variability has been detected in the flux emitted by the central star with a period of 639 ± 4 days, in good agreement with determinations in the literature. Variability is also detected in the bow shock around CW Leo th…
The XMM deep survey in the CDF-S. II. A 9-20 keV selection of heavily obscured active galaxies at z > 1.7
Brandt, W. N.; Vignali, C.; Gilli, R. +10 more
We present results on a search of heavily obscured active galaxies z > 1.7 using the rest-frame 9-20 keV excess for X-ray sources detected in the deep XMM-CDFS survey. Out of 176 sources selected with the conservative detection criteria (>8σ) in the first source catalogue of Ranalli et al. (in prep.), 46 objects lie in the redshift range of …
Modelling of the ultraviolet and visual SED variability in the hot magnetic Ap star CU Virginis
Shulyak, D.; Krtička, J.; Lüftinger, T. +4 more
Context. The spectral energy distribution (SED) in chemically peculiar stars may be significantly affected by their abundance anomalies. The observed SED variations are usually assumed to be a result of inhomogeneous surface distribution of chemical elements, flux redistribution and stellar rotation. However, the direct evidence for this is still …
Identification of HESS J1303-631 as a pulsar wind nebula through γ-ray, X-ray, and radio observations
Klochkov, D.; Santangelo, A.; Quirrenbach, A. +195 more
Aims: The previously unidentified very high-energy (VHE; E > 100 GeV) γ-ray source HESS J1303-631, discovered in 2004, is re-examined including new data from the H.E.S.S. Cherenkov telescope array in order to identify this object. Archival data from the XMM-Newton X-ray satellite and from the PMN radio survey are also examined.
Method…
Expansion of magnetic clouds in the outer heliosphere
Rodriguez, L.; Gulisano, A. M.; Démoulin, P. +1 more
Context. A large amount of magnetized plasma is frequently ejected from the Sun as coronal mass ejections (CMEs). Some of these ejections are detected in the solar wind as magnetic clouds (MCs) that have flux rope signatures.
Aims: Magnetic clouds are structures that typically expand in the inner heliosphere. We derive the expansion propertie…
The relationship between γ Cassiopeiae's X-ray emission and its circumstellar environment
Motch, C.; Pollmann, E.; Smith, M. A. +17 more
γ Cas is the prototypical classical Be star and is recently best known for its variable hard X-ray emission. To elucidate the reasons for this emission, we mounted a multiwavelength campaign in 2010 centered around four XMM-Newton observations. The observational techniques included long baseline optical interferometry (LBOI) from two instruments a…