References of "2010"
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See detailLong-term magnetic field monitoring of the sun-like star ξ Bootis A
Morgenthaler, A.; Petit, P.; Aurière, M. et al

in Boissier, S.; Heydari-Malayeri, M.; Samadi, R. (Eds.) et al SF2A-2010: Proceedings of the Annual meeting of the French Society of Astronomy and Astrophysics (2010, December 01)

Phase-resolved observations of the solar-type star ξ Bootis A were obtained using the Narval spectropolarimeter at Telescope Bernard Lyot (Pic du Midi, France) during years 2007, 2008, 2009 and 2010. The ... [more ▼]

Phase-resolved observations of the solar-type star ξ Bootis A were obtained using the Narval spectropolarimeter at Telescope Bernard Lyot (Pic du Midi, France) during years 2007, 2008, 2009 and 2010. The data sets enable us to study both the rotational and the long-term evolution of various activity tracers. Here, we focus on the large-scale photospheric magnetic field (reconstructed by Zeeman-Doppler Imaging), the Zeeman broadening of the FeI 846.84 nm magnetic line, and the chromospheric CaII H and Hα emission. [less ▲]

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See detailWASP-22 b: A Transiting "Hot Jupiter" Planet in a Hierarchical Triple System
Maxted, P. F. L.; Anderson, D. R.; Gillon, Michaël ULg et al

in Astrophysical Journal (2010), 140(6), 2007-2012

We report the discovery of a transiting planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T[SUB]eff[/SUB] = 6000 ± 100 K, [Fe/H] = –0.05 ± 0.08 ... [more ▼]

We report the discovery of a transiting planet orbiting the star TYC 6446-326-1. The star, WASP-22, is a moderately bright (V = 12.0) solar-type star (T[SUB]eff[/SUB] = 6000 ± 100 K, [Fe/H] = –0.05 ± 0.08). The light curve of the star obtained with the WASP-South instrument shows periodic transit-like features with a depth of about 1% and a duration of 0.14 days. The presence of a transit-like feature in the light curve is confirmed using z-band photometry obtained with Faulkes Telescope South. High-resolution spectroscopy obtained with the CORALIE and HARPS spectrographs confirms the presence of a planetary mass companion with an orbital period of 3.533 days in a near-circular orbit. From a combined analysis of the spectroscopic and photometric data assuming that the star is a typical main-sequence star we estimate that the planet has a mass M [SUB]p[/SUB] = 0.56 ± 0.02M [SUB]Jup[/SUB] and a radius R [SUB]p[/SUB] = 1.12 ± 0.04R [SUB]Jup[/SUB]. In addition, there is a linear trend of 40 m s[SUP]–1[/SUP] yr[SUP]–1[/SUP] in the radial velocities measured over 16 months, from which we infer the presence of a third body with a long-period orbit in this system. The companion may be a low mass M-dwarf, a white dwarf, or a second planet. [less ▲]

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See detail"Politique linguistique et organisation des centres de langues dans les universités"
Defays, Jean-Marc ULg

Scientific conference (2010, December 01)

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See detailInference from adiabatic analysis of solar-like oscillations in red giants
Montalban Iglesias, Josefa ULg; Miglio, Andrea ULg; Noels-Grötsch, Arlette ULg et al

in Astronomische Nachrichten (2010), 331

The clear detection with CoRoT and Kepler of radial and non-radial solar-like oscillations in many red giants paves the way to seismic inferences on the structure of such stars. We present an overview of ... [more ▼]

The clear detection with CoRoT and Kepler of radial and non-radial solar-like oscillations in many red giants paves the way to seismic inferences on the structure of such stars. We present an overview of the properties of the adiabatic frequencies and frequency separations of radial and non-radial oscillation modes, highlighting how their detection allows a deeper insight into the properties of the internal structure of red giants. In our study we consider models of red giants in different evolutionary stages, as well as of different masses and chemical composition. We describe how the large and small separations computed with radial modes and with non-radial modes mostly trapped in the envelope depend on the stellar global parameters and evolutionary state, and we compare our theoretical predictions and first Kepler data.Finally, we find that the properties of dipole modes constitute a promising seismic diagnostic of the evolutionary state of red-giant stars. [less ▲]

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See detailDe la participation au projet à l’implication dans le territoire
Dawance, Sophie ULg; Ribeiro Amélia, De Rijck Kim

Scientific conference (2010, December 01)

Nul ne nie aujourd’hui l’intérêt d’associer les habitants et usagers au processus d’élaboration d’un projet de rénovation de leur quartier. Cependant, force est de constater que les délais et modalités de ... [more ▼]

Nul ne nie aujourd’hui l’intérêt d’associer les habitants et usagers au processus d’élaboration d’un projet de rénovation de leur quartier. Cependant, force est de constater que les délais et modalités de la participation classique ne permettent pas à certains types de public de s’exprimer et ne laissent pas le temps de la maturation et de l’appropriation. Il faut donc inventer des formes d’intervention qui permettent l’implication des habitants dans la ville dans la durée et qui participent à l’émergence d’une véritable culture de la participation. Community land trust, potager collectif, urbanisme temporaire, budgets participatifs… autant de projets qui permettent aux citoyens de devenir acteur et de tisser des liens intimes avec leur territoire. [less ▲]

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See detailOscillations in rapidly rotating stars
Reese, Daniel ULg

in Astronomische Nachrichten (2010, December 01), 331

Spurred by the spectroscopic and interferometric observations of rapidly rotating stars and the highly accurate pulsation data coming from asteroseismology space missions, theoreticians have spent many ... [more ▼]

Spurred by the spectroscopic and interferometric observations of rapidly rotating stars and the highly accurate pulsation data coming from asteroseismology space missions, theoreticians have spent many years developing models for such stars and studying their oscillations. This has led to the discovery of new phenomena and new types of pulsation modes. In what follows, a review is given of the different methods used to model the effects of rotation on stellar pulsations, as well as a description of these effects on inertial, gravito-inertial, r and acoustic modes. [less ▲]

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See detailVers une relance du partenariat stratégique de l’Union européenne avec l’Amérique latine ?
Santander, Sébastian ULg

Scientific conference (2010, December 01)

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See detailPlasma Motion and Kinematics in Cool and Hot Stars
Güdel, Manuel; Nazé, Yaël ULg

in Space Science Reviews (2010), 157

The environments of both hot and cool stars are the sites of highly dynamic processes involving motion of gas and plasma in winds, flows across shocks, plasma motions in closed magnetic fields, or streams ... [more ▼]

The environments of both hot and cool stars are the sites of highly dynamic processes involving motion of gas and plasma in winds, flows across shocks, plasma motions in closed magnetic fields, or streams along magnetospheric accretion funnels. X-ray spectroscopy has opened new windows toward the study of these processes. Kinematics are evident in line shifts and line broadening, and also more indirectly through the analysis and interpretation of density-sensitive lines. In hot stellar winds, expanding-wind kinematics are directly seen in broadened lines although the broadening has turned out to often be smaller than anticipated, and some lines are so narrow that coronal models have been revived. Although X-ray spectra of cool stars have shown line shifts and broadening due to the kinematics of the entire corona, e.g., in binary systems, intrinsic mass motions are challenging to observe at the presently available resolution. Much indirect evidence for mass motion in magnetic coronae is nevertheless available. And finally, spectral diagnostics has also led to a new picture of X-ray production in accreting pre-main sequence stars where massive accretion flows collide with the photospheric gas, producing shocks in which gas is heated to high temperatures. We summarize evidence for the above mechanisms based on spectroscopic data from XMM-Newton and Chandra. [less ▲]

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See detailAsteroseismology of OB stars with CoRoT
Degroote, P.; Aerts, C.; Samadi, R. et al

in Astronomische Nachrichten (2010), 331

The CoRoT satellite is revolutionizing the photometric study of massive O-type and B-type stars. During its long runs, CoRoT observed the entire main sequence B star domain, from typical hot β Cep stars ... [more ▼]

The CoRoT satellite is revolutionizing the photometric study of massive O-type and B-type stars. During its long runs, CoRoT observed the entire main sequence B star domain, from typical hot β Cep stars, via cooler hybrid p- and g-mode pulsators to the SPB stars near the edge of the instability strip. CoRoT lowers the sensitivity barrier from the typical mmag-precision reached from the ground, to the μmag-level reached from space. Within the wealth of detected and identified pulsation modes, relations have been found in the form of multiplets, combination of frequencies, and frequency- and period spacings. This wealth of observational evidence is finally providing strong constraints to test current models of the internal structure and pulsations of hot stars. Aside from the expected opacity driven modes with infinite lifetime, other unexpected types of variability are detected in massive stars, such as modes of stochastic nature. The simultaneous observation of all these light curve characteristics implies a challenge for both observational asteroseismology and stellar modelling. The CoRoT space mission was developed and is operated by the French space agency CNES, with participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain. [less ▲]

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See detailAsteroseismology of solar-type stars with Kepler: III. Ground-based data
Molenda-Żakowicz, J.; Bruntt, H.; Sousa, S. et al

in Astronomische Nachrichten (2010), 331

We report on the ground-based follow-up program of spectroscopic and photometric observations of solar-like asteroseismic targets for the Kepler space mission. These stars constitute a large group of more ... [more ▼]

We report on the ground-based follow-up program of spectroscopic and photometric observations of solar-like asteroseismic targets for the Kepler space mission. These stars constitute a large group of more than a thousand objects which are the subject of an intensive study by the Kepler Asteroseismic Science Consortium Working Group 1 (KASC WG-1). In the current work we will discuss the methods we use to determine the fundamental stellar atmospheric parameters using high-quality stellar spectra. These provide essential constraints for the asteroseismic modelling and make it possible to verify the parameters in the Kepler Input Catalogue (KIC). [less ▲]

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See detailGround-based follow-up in relation to Kepler asteroseismic investigation
Uytterhoeven, K.; Briquet, Maryline ULg; Bruntt, H. et al

in Astronomische Nachrichten (2010), 331

The Kepler space mission, successfully launched in March 2009, is providing continuous and high-precision photometry of thousands of stars simultaneously. The uninterrupted time-series of stars of all ... [more ▼]

The Kepler space mission, successfully launched in March 2009, is providing continuous and high-precision photometry of thousands of stars simultaneously. The uninterrupted time-series of stars of all known pulsation types are a precious source for asteroseismic studies. The Kepler data do not provide information on the physical parameters, such as T_eff, log g, metallicity, and v sin i, which are crucial for successful asteroseismic modelling. Additional ground-based time-series data are needed to characterize mode parameters in several types of pulsating stars. Therefore, ground-based multi-colour photometry and mid/high-resolution spectroscopy are needed to complement the space data. We present ground-based activities within KASC on selected asteroseismic Kepler targets of several pulsation types. Based on observations made with the Isaac Newton Telescope and William Herschel Telescope operated by the Isaac Newton Group, with the Nordic Optical Telescope, operated jointly by Denmark, Finland, Iceland, Norway, and Sweden, with the Italian Telescopio Nazionale Galileo (TNG) operated by the Fundación Galileo Galilei of the INAF (Istituto Nazionale di Astrofisica), and with the Mercator telescope, operated by the Flemish Community, all on the island of La Palma at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias (IAC). Based on observations made with the IAC-80 operated on the island of Tenerife by the IAC at the Spanish Observatorio del Teide. Also based on observations taken at the observatories of Sierra Nevada, San Pedro Mártir, Vienna, Xinglong, Apache Point, Lulin, Tautenburg, McDonald, Skinakas, Pic du Midi, Mauna Kea, Steward Observatory, Mt. Wilson, Białków Observatory of the Wrocław University, Piszkésteto Mountain Station, and Observatoire de Haute Provence. Based on spectra taken at the Loiano (INAF - OA Bologna), Serra La Nave (INAF - OA Catania) and Asiago (INAF - OA Padova) observatories. Also based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck-Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC). We acknowledge with thanks the variable star observations from the AAVSO International Database contributed by observers worldwide and used in this research. Funding for the Kepler mission is provided by NASA's Science Mission Directorate. We thank the entire Kepler team for the development and operations of this outstanding mission. [less ▲]

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See detailTowards ensemble asteroseismology of the young open clusters χ Persei and NGC 6910
Saesen, S.; Pigulski, A.; Carrier, F. et al

in Astronomische Nachrichten (2010), 331

As a result of the variability survey in χ Persei and NGC 6910, the number of β Cep stars that are members of these two open clusters is increased to twenty stars, nine in NGC 6910 and eleven in χ Persei ... [more ▼]

As a result of the variability survey in χ Persei and NGC 6910, the number of β Cep stars that are members of these two open clusters is increased to twenty stars, nine in NGC 6910 and eleven in χ Persei. We compare pulsational properties, in particular the frequency spectra, of β Cep stars in both clusters and explain the differences in terms of the global parameters of the clusters. We also indicate that the more complicated pattern of the variability among B-type stars in χ Persei is very likely caused by higher rotational velocities of stars in this cluster. We conclude that the sample of pulsating stars in the two open clusters constitutes a very good starting point for the ensemble asteroseismology of β Cep-type stars and maybe also for other B-type pulsators. [less ▲]

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See detailInteractions in Massive Binary Systems
Rauw, Grégor ULg

in Prša, Andrej; Zejda, Miloslav (Eds.) Binaries - Key to Comprehension of the Universe (2010, December 01)

In binary systems consisting of two massive stars, the interaction of the powerful stellar winds of the two components produces signatures over a broad range of wavelengths. Many observational and ... [more ▼]

In binary systems consisting of two massive stars, the interaction of the powerful stellar winds of the two components produces signatures over a broad range of wavelengths. Many observational and theoretical studies of this phenomenon have been performed over the last two decades. In very close massive binary systems, mass exchange due to Roche lobe overflow can also occur and the signatures of the two phenomena are sometimes hard to distinguish. In this review, I discuss some recent developments in the study of both phenomena. [less ▲]

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See detailExoplanet discoveries with the CoRoT space observatory
Lammer, H.; Dvorak, R.; Deleuil, M. et al

in Solar System Research (2010), 44

The CoRoT space observatory is a project which is led by the French space agency CNES and leading space research institutes in Austria, Brazil, Belgium, Germany and Spain and also the European Space ... [more ▼]

The CoRoT space observatory is a project which is led by the French space agency CNES and leading space research institutes in Austria, Brazil, Belgium, Germany and Spain and also the European Space Agency ESA. CoRoT observed since its launch in December 27, 2006 about 100 000 stars for the exoplanet channel, during 150 days uninterrupted high-precision photometry. Since the The CoRoT-team has several exoplanet candidates which are currently analyzed under its study, we report here the discoveries of nine exoplanets which were observed by CoRoT. Discovered exoplanets such as CoRoT-3b populate the brown dwarf desert and close the gap of measured physical properties between usual gas giants and very low mass stars. CoRoT discoveries extended the known range of planet masses down to about 4.8 Earth-masses (CoRoT-7b) and up to 21 Jupiter masses (CoRoT-3b), the radii to about 1.68 × 0.09 R [SUB]Earth[/SUB] (CoRoT-7b) and up to the most inflated hot Jupiter with 1.49 × 0.09 R [SUB]Earth[/SUB] found so far (CoRoT-1b), and the transiting exoplanet with the longest period of 95.274 days (CoRoT-9b). Giant exoplanets have been detected at low metallicity, rapidly rotating and active, spotted stars. Two CoRoT planets have host stars with the lowest content of heavy elements known to show a transit hinting towards a different planethost-star-metallicity relation then the one found by radial-velocity search programs. Finally the properties of the CoRoT-7b prove that rocky planets with a density close to Earth exist outside the Solar System. Finally the detection of the secondary transit of CoRoT-1b at a sensitivity level of 10[SUP]-5[/SUP] and the very clear detection of the "super-Earth" CoRoT-7b at 3.5 × 10[SUP]-4[/SUP] relative flux are promising evidence that the space observatory is being able to detect even smaller exoplanets with the size of the Earth. [less ▲]

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See detailRehabilitation in osteoporosis
Bruyère, Olivier ULg

in Proceedings of the annual congress of the Royal Belgian Society of Physical and Rehabilitation medicine (2010, December)

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See detailWhat can we learn from the auroral footprints of the Jovian moons? (Invited)
Bonfond, Bertrand ULg

Conference (2010, December)

The signature of electromagnetic interaction between the moons Io, Europa and Ganymede and the Jovian magnetosphere can be observed on Jupiter’s polar ionosphere in the form of auroral footprints. The ... [more ▼]

The signature of electromagnetic interaction between the moons Io, Europa and Ganymede and the Jovian magnetosphere can be observed on Jupiter’s polar ionosphere in the form of auroral footprints. The observation campaigns carried out during the past few years by the Hubble Space Telescope in the Far UV domain provided not only a high spatial and temporal resolution but also an unprecedented System III longitude coverage. Consequently, these recent observations of the morphology and the dynamics of the footprints proved to be very powerful tools to probe these interactions. For example, the locations of the satellite footprints have been used as a valuable constraint for building Jovian magnetic field models. Moreover, analysis of the multiplicity of the Io footprint spots as well as their relative motion lead to new conclusions on the electron acceleration processes. The altitude of the Io footprint has also been used to infer the typical energy of the impinging electrons. Finally, the study of the three-dimensional shape and of the brightness of the different sub-structures of the footprints provides important clues on the processes at play between Io and the Jovian ionosphere. On the theoretical side, considerable efforts have also been recently carried out in order to model the propagation of the Alfvén waves generated at Io and the subsequent acceleration of auroral electrons. Coupled with HST images, radio decametric measurements and in situ data from the Galileo spacecraft, these advances provide a brand new understanding of the satellite footprints. [less ▲]

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See detailUne identité tranquille
Jacquemain, Marc ULg

Article for general public (2010)

L'article défend l'idée que l'identité wallonne s'appuie historiquement sur une revendication sociale plutôt que culturelle: disposer d'une autonomie de gestion pour mener une politique économique plus ... [more ▼]

L'article défend l'idée que l'identité wallonne s'appuie historiquement sur une revendication sociale plutôt que culturelle: disposer d'une autonomie de gestion pour mener une politique économique plus favorable à la région. Cette histoire protège l'identité wallonne de la "passion nationaliste" qui gangrène beaucoup de régions d'Europe et lui donne son contenu spécifique : le consensus social-démocrate. [less ▲]

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See detail3D information is valuable for the detection of humans in video streams
Pierard, Sébastien ULg; Lejeune, Antoine ULg; Van Droogenbroeck, Marc ULg

in 3D Stereo Media (2010, December)

In this paper, we propose a technique based on 3D information (also called depth or range) for the detection of humans. First, a background subtraction technique operates to detect the silhouettes of ... [more ▼]

In this paper, we propose a technique based on 3D information (also called depth or range) for the detection of humans. First, a background subtraction technique operates to detect the silhouettes of humans and objects moving in the scene. Then, a machine learning algorithm is used to predict if a silhouette annotated with depth matches a human silhouette or not. The complete method is designed to cope with defects introduced during the segmentation step. Results, obtained on computer generated data, show that 3D depth data is a valuable information for detecting humans in that it improves over techniques based on binary silhouettes. In our experiments, we have reached an accuracy of 99.9% thanks to the depth information. [less ▲]

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