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See detailCoRoT's view of newly discovered B-star pulsators: results for 358 candidate B pulsators from the initial run's exoplanet field data
Degroote, P.; Aerts, C.; Ollivier, M. et al

in Astronomy and Astrophysics (2009), 506

Context: We search for new variable B-type pulsators in the CoRoT data assembled primarily for planet detection, as part of CoRoT's additional programme. <BR />Aims: We aim to explore the properties of ... [more ▼]

Context: We search for new variable B-type pulsators in the CoRoT data assembled primarily for planet detection, as part of CoRoT's additional programme. <BR />Aims: We aim to explore the properties of newly discovered B-type pulsators from the uninterrupted CoRoT space-based photometry and to compare them with known members of the β Cep and slowly pulsating B star (SPB) classes. <BR />Methods: We developed automated data analysis tools that include algorithms for jump correction, light-curve detrending, frequency detection, frequency combination search, and for frequency and period spacing searches. <BR />Results: Besides numerous new, classical, slowly pulsating B stars, we find evidence for a new class of low-amplitude B-type pulsators between the SPB and δ Sct instability strips, with a very broad range of frequencies and low amplitudes, as well as several slowly pulsating B stars with residual excess power at frequencies typically a factor three above their expected g-mode frequencies. <BR />Conclusions: The frequency data we obtained for numerous new B-type pulsators represent an appropriate starting point for further theoretical analyses of these stars, once their effective temperature, gravity, rotation velocity, and abundances will be derived spectroscopically in the framework of an ongoing FLAMES survey at the VLT. The CoRoT space mission was developed and is operated by the French space agency CNES, with the participation of ESA's RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain. All frequency tables, including the identification of combination frequencies, are only available as online material. Frequency Tables are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/506/471 Bâtiment 121, 91405, Orsay Cedex, France. Postdoctoral Researcher, Fonds de la Recherche Scientifique - FNRS, Belgium. Postdoctoral Fellow of the Fund for Scientific Research, Flanders. [less ▲]

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See detailPersonalisation of learning in virtual learning environments
Verpoorten, Dominique ULg; Glahn, C.; Kravcik, M. et al

in Lecture Notes in Computer Science (2009), 5794

Personalization of learning has become a prominent issue in the educational field, at various levels. This article elaborates a different view on personalisation than what usually occurs in this area. Its ... [more ▼]

Personalization of learning has become a prominent issue in the educational field, at various levels. This article elaborates a different view on personalisation than what usually occurs in this area. Its baseline is that personalisation occurs when learning turns out to become personal in the learner's mind. Through a literature survey, we analyze constitutive dimensions of this inner sense of personalisation. Here, we devote special attention to confronting learners with tracked information. Making their personal interaction footprints visible contrasts with the back-office usage of this data by researchers, instructors or adaptive systems. We contribute a prototype designed for the Moodle platform according to the conceptual approach presented here. [less ▲]

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See detailAbundance analysis of prime B-type targets for asteroseismology. II. B6-B9.5 stars in the field of view of the CoRoT satellite
Niemczura, E.; Morel, Thierry ULg; Aerts, C.

in Astronomy and Astrophysics (2009), 506

Context: <BR />Aims: The main goal of the ground-based seismology support program for the CoRoT mission was to obtain photometric and spectroscopic data for stars in the fields monitored by the satellite ... [more ▼]

Context: <BR />Aims: The main goal of the ground-based seismology support program for the CoRoT mission was to obtain photometric and spectroscopic data for stars in the fields monitored by the satellite. These ground-based observations were collected in the GAUDI archive. High-resolution spectra of more than 200 B-type stars are available in this database, and about 45% of them is analysed here. <BR />Methods: To derive the effective temperature of the stars, we used photometric indices. Surface gravities were obtained by comparing observed and theoretical Balmer line profiles. To determine the chemical abundances and rotational velocities, we used a spectrum synthesis method, which consisted of comparing the observed spectrum with theoretical ones based on the assumption of LTE. <BR />Results: Atmospheric parameters, chemical abundances, and rotational velocities were determined for 89 late-B stars. The dominant species in their spectra are iron-peak elements. The average Fe abundance is 7.24 ± 0.45 dex. The average rotational velocity is 126 km s[SUP]-1[/SUP], but there are 13 and 20 stars with low and moderate V sin i values, respectively. The analysis of this sample of 89 late B-type stars reveals many chemically peculiar (CP) stars. Some of them were previously known, but at least 9 new CP candidates, among which at least two HgMn stars, are identified in our study. These CP stars as a group exhibit V sin i values lower than the stars with normal surface chemical composition. Atmospheric parameters and abundance analysis results are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/506/213 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. Tables [see full textsee full text] and [see full textsee full text] are only available in electronic form at http://www.aanda.org [less ▲]

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See detailTheoretical amplitudes and lifetimes of non-radial solar-like oscillations in red giants
Dupret, Marc-Antoine ULg; Belkacem, Kevin ULg; Samadi, Réza et al

in Astronomy and Astrophysics (2009), 506

Context: Solar-like oscillations have been observed in numerous red giants from ground and from space. An important question arises: could we expect to detect non-radial modes probing the internal ... [more ▼]

Context: Solar-like oscillations have been observed in numerous red giants from ground and from space. An important question arises: could we expect to detect non-radial modes probing the internal structure of these stars? <BR />Aims: We investigate under what physical circumstances non-radial modes could be observable in red giants; what would be their amplitudes, lifetimes and heights in the power spectrum (PS)? <BR />Methods: Using a non-radial non-adiabatic pulsation code including a non-local time-dependent treatment of convection, we compute the theoretical lifetimes of radial and non-radial modes in several red giant models. Next, using a stochastic excitation model, we compute the amplitudes of these modes and their heights in the PS. <BR />Results: Distinct cases appear. Case A corresponds to subgiants and stars at the bottom of the ascending giant branch. Our results show that the lifetimes of the modes are mainly proportional to the inertia I, which is modulated by the mode trapping. The predicted amplitudes are lower for non-radial modes. But the height of the peaks in the PS are of the same order for radial and non-radial modes as long as they can be resolved. The resulting frequency spectrum is complex. Case B corresponds to intermediate models in the red giant branch. In these models, the radiative damping becomes high enough to destroy the non-radial modes trapped in the core. Hence, only modes trapped in the envelope have significant heights in the PS and could be observed. The resulting frequency spectrum of detectable modes is regular for â =0 and 2, but a little more complex for â =1 modes because of less efficient trapping. Case C corresponds to models of even higher luminosity. In these models the radiative damping of non-radial modes is even larger than in the previous case and only radial and non-radial modes completely trapped in the envelope could be observed. The frequency pattern is very regular for these stars. The comparison between the predictions for radial and non-radial modes is very different if we consider the heights in the PS instead of the amplitudes. This is important as the heights (not the amplitudes) are used as detection criterion. CIFIST Marie Curie Excellence Team. [less ▲]

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See detailOn posterior probability and significance level: application to the power spectrum of HD 49 933 observed by CoRoT
Appourchaux, T.; Samadi, R.; Dupret, Marc-Antoine ULg

in Astronomy and Astrophysics (2009), 506

Context: The CoRoT mission provides asteroseismic data of very high quality allowing one to adopt new statistical approaches for mode detection in power spectra, especially with respect to testing the ... [more ▼]

Context: The CoRoT mission provides asteroseismic data of very high quality allowing one to adopt new statistical approaches for mode detection in power spectra, especially with respect to testing the null hypothesis (H{0}, which assumes that what is observed is pure noise). Aims: We emphasize that the significance level when rejecting the null hypothesis can lead to the incorrect conclusion that the H{0} hypothesis is unlikely to occur at that significance level. We demonstrate that the significance level is unrelated to the posterior probability of H{0}, given the observed data set, and that this posterior probability is very much higher than implied by the significance level. Methods: We use Bayes theorem to derive the posterior probability of that H{0} is true assuming an alternative hypothesis H{1} that a mode is present, taking some prior for the mode height, mode amplitude and linewidth. Results: We compute the posterior probability of H{0} for the p modes detected on HD 49 933 by CoRoT. Conclusions: We conclude that the posterior probability of H{0} provide a much more conservative quantification of the mode detection than the significance level. This framework can be applied to any similar stellar power spectra obtained to complete asteroseismology. The CoRoT space mission, launched on 2006 December 27, was developed and is operated by the CNES, with participation of the Science Programs of ESA, ESA's RSSD, Austria, Belgium, Brazil, Germany and Spain. [less ▲]

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See detailRemoving systematics from the CoRoT light curves. I. Magnitude-dependent zero point
Mazeh, T.; Guterman, P.; Aigrain, S. et al

in Astronomy and Astrophysics (2009), 506

This paper presents an analysis that searched for systematic effects within the CoRoT exoplanet field light curves. The analysis identified a systematic effect that modified the zero point of most CoRoT ... [more ▼]

This paper presents an analysis that searched for systematic effects within the CoRoT exoplanet field light curves. The analysis identified a systematic effect that modified the zero point of most CoRoT exposures as a function of stellar magnitude. We could find this effect only after preparing a set of learning light curves that were relatively free of stellar and instrumental noise. Correcting for this effect, rejecting outliers that appear in almost every exposure, and applying SysRem, reduced the stellar RMS by about 20%, without attenuating transit signals. The CoRoT space mission, launched on December 27th 2006, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil, ESA, Germany, and Spain. CoRoT data become publicly available one year after release to the Co-Is of the mission from the CoRoT archive: http://idoc-corot.ias.u-psud.fr/. [less ▲]

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See detailRate and nature of false positives in the CoRoT exoplanet search
Almenara, J. M.; Deeg, H. J.; Aigrain, S. et al

in Astronomy and Astrophysics (2009), 506

Context: The CoRoT satellite searches for planets by applying the transit method, monitoring up to 12 000 stars in the galactic plane for 150 days in each observing run. This search is contaminated by a ... [more ▼]

Context: The CoRoT satellite searches for planets by applying the transit method, monitoring up to 12 000 stars in the galactic plane for 150 days in each observing run. This search is contaminated by a large fraction of false positives, caused by different eclipsing binary configurations that might be confused with a transiting planet. <BR />Aims: We evaluate the rates and nature of false positives in the CoRoT exoplanets search and compare our results with semiempirical predictions. <BR />Methods: We consider the detected binary and planet candidates in the first three extended CoRoT runs, and classify the results of the follow-up observations completed to verify their planetary nature. We group the follow-up results into undiluted binaries, diluted binaries, and planets and compare their abundances with predictions from the literature. <BR />Results: 83% of the initial detections are classified as false positives using only the CoRoT light-curves, the remaining 17% require follow-up observations. Finally, 12% of the candidates in the follow-up program are planets. The shape of the overall distribution of the false positive rate follows previous predictions, except for candidates with transit depths below about 0.4%. For candidates with transit depths in the range from 0.1-0.4%, CoRoT detections are nearly complete, and this difference from predictions is probably real and dominated by a lower than expected abundance of diluted eclipsing binaries. The CoRoT space mission, launched on December 27th 2006, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil , ESA (RSSD and Science Programme), Germany and Spain. [less ▲]

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See detailPlanetary transit candidates in the CoRoT initial run: resolving their nature
Moutou, C.; Pont, F.; Bouchy, F. et al

in Astronomy and Astrophysics (2009), 506

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 ... [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 measurements. Two giant planets were identified and fully characterized. Nineteen binaries are recognized, from which 10 are background eclipsing binaries in the CoRoT mask or triple systems, diluted by the main CoRoT target. Eight cases remain of unclear origin, one of them still being a planetary candidate. Comparison with simulations shows that the actual threshold of confirmed planet detection in this field does not yet fulfill the expectations, and a number of reasons are invoked, like the ranking process based on lightcurve analyses, and the strategy and limits of follow-up observations for targets fainter than magnitude 15. Based on data obtained at Observatoire de Haute Provence with SOPHIE and with HARPS on the ESO 3.6 m telescope at La Silla Observatory. The CoRoT space mission, launched on December 27th 2006, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil , ESA (RSSD and Science Programme), Germany and Spain. Tables 2 to 13, 15 to 17 and Figs. 4 to 7 are only available in electronic form at http://www.aanda.org [less ▲]

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See detailThe CoRoT-7 planetary system: two orbiting super-Earths
Queloz, D.; Bouchy, F.; Moutou, C. et al

in Astronomy and Astrophysics (2009), 506

We report on an intensive observational campaign carried out with HARPS at the 3.6 m telescope at La Silla on the star CoRoT-7. Additional simultaneous photometric measurements carried out with the Euler ... [more ▼]

We report on an intensive observational campaign carried out with HARPS at the 3.6 m telescope at La Silla on the star CoRoT-7. Additional simultaneous photometric measurements carried out with the Euler Swiss telescope have demonstrated that the observed radial velocity variations are dominated by rotational modulation from cool spots on the stellar surface. Several approaches were used to extract the radial velocity signal of the planet(s) from the stellar activity signal. First, a simple pre-whitening procedure was employed to find and subsequently remove periodic signals from the complex frequency structure of the radial velocity data. The dominant frequency in the power spectrum was found at 23 days, which corresponds to the rotation period of CoRoT-7. The 0.8535 day period of CoRoT-7b planetary candidate was detected with an amplitude of 3.3 m s[SUP]-1[/SUP]. Most other frequencies, some with amplitudes larger than the CoRoT-7b signal, are most likely associated with activity. A second approach used harmonic decomposition of the rotational period and up to the first three harmonics to filter out the activity signal from radial velocity variations caused by orbiting planets. After correcting the radial velocity data for activity, two periodic signals are detected: the CoRoT-7b transit period and a second one with a period of 3.69 days and an amplitude of 4 m s[SUP]-1[/SUP]. This second signal was also found in the pre-whitening analysis. We attribute the second signal to a second, more remote planet CoRoT-7c . The orbital solution of both planets is compatible with circular orbits. The mass of CoRoT-7b is 4.8±0.8 (M[SUB]â [/SUB]) and that of CoRoT-7c is 8.4± 0.9 (M[SUB]â [/SUB]), assuming both planets are on coplanar orbits. We also investigated the false positive scenario of a blend by a faint stellar binary, and this may be rejected by the stability of the bisector on a nightly scale. According to their masses both planets belong to the super-Earth planet category. The average density of CoRoT-7b is Ï =5.6± 1.3 g cm[SUP]-3[/SUP], similar to the Earth. The CoRoT-7 planetary system provides us with the first insight into the physical nature of short period super-Earth planets recently detected by radial velocity surveys. These planets may be denser than Neptune and therefore likely made of rocks like the Earth, or a mix of water ice and rocks. Based on observations made with HARPS spectrograph on the 3.6-m ESO telescope and the EULER Swiss telescope at La Silla Observatory, Chile. The HARPS results presented in this paper (Appendix A) are available in electronic form at http://www.aanda.org and at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/506/303 [less ▲]

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See detailTransiting exoplanets from the CoRoT space mission. VII. The ``hot-Jupiter''-type planet CoRoT-5b
Rauer, H.; Queloz, D.; Csizmadia, Szilard et al

in Astronomy and Astrophysics (2009), 506

Aims: The CoRoT space mission continues to photometrically monitor about 12 000 stars in its field-of-view for a series of target fields to search for transiting extrasolar planets ever since 2007. Deep ... [more ▼]

Aims: The CoRoT space mission continues to photometrically monitor about 12 000 stars in its field-of-view for a series of target fields to search for transiting extrasolar planets ever since 2007. Deep transit signals can be detected quickly in the â alarm-modeâ in parallel to the ongoing target field monitoring. CoRoT's first planets have been detected in this mode. <BR />Methods: The CoRoT raw lightcurves are filtered for orbital residuals, outliers, and low-frequency stellar signals. The phase folded lightcurve is used to fit the transit signal and derive the main planetary parameters. Radial velocity follow-up observations were initiated to secure the detection and to derive the planet mass. <BR />Results: We report the detection of CoRoT-5b, detected during observations of the LRa01 field, the first long-duration field in the galactic anti-center direction. CoRoT-5b is a â hot Jupiter-typeâ planet with a radius of 1.388[SUP]+0.046[/SUP][SUB]-0.047[/SUB] R_Jup, a mass of 0.467[SUP]+0.047[/SUP][SUB]-0.024[/SUB] M_Jup, and therefore, a mean density of 0.217[SUP]+0.031[/SUP][SUB]-0.025[/SUB] g cm[SUP]-3[/SUP]. The planet orbits an F9V star of 14.0 mag in 4.0378962 ± 0.0000019 days at an orbital distance of 0.04947[SUP]+0.00026[/SUP][SUB]-0.00029[/SUB] AU. Observations made with SOPHIE spectrograph at the Observatoire de Haute Provence (07B.PNP.MOUT), France, and HARPS spectrograph at ESO La Silla Observatory (072.C-0488(E), 082.C-0312(A)), and partly based on observations made at the Anglo-Australian Telescope. The CoRoT space mission, launched on December 27, 2006, was developed and is operated by CNES, with the contribution of Austria, Belgium, Brasil, ESA, Germany, and Spain. [less ▲]

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See detailPlanetary transit candidates in CoRoT-LRc01 field
Cabrera, J.; Fridlund, M.; Ollivier, M. et al

in Astronomy and Astrophysics (2009), 506

Aims: We present here the list of planetary transit candidates detected in the first long run observed by CoRoT: LRc01, towards the galactic center in the direction of Aquila, which lasted from May to ... [more ▼]

Aims: We present here the list of planetary transit candidates detected in the first long run observed by CoRoT: LRc01, towards the galactic center in the direction of Aquila, which lasted from May to October 2007. <BR />Methods: we analyzed 3719 (33%) sources in the chromatic bands and 7689 in the monochromatic band. Instrumental noise and the stellar variability were treated with several detrending tools, on which subsequently several transit search algorithms were applied. <BR />Results: Forty two sources were classified as planetary transit candidates and up to now 26 cases have been solved. One planet (CoRoT-2b) and one brown-dwarf (CoRoT-3b) have been the subjects of detailed publications. The CoRoT space mission, launched on December 27 2006, was developed and is operated by CNES, with contributions from Austria, Belgium, Brazil, ESA, Germany and Spain. The first CoRoT data are available to the community from the CoRoT archive: http://idoc-corot.ias.u-psud.fr. [less ▲]

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See detailPost-AGB stars with hot circumstellar dust: binarity of the low-amplitude pulsators
van Winckel, H.; Lloyd Evans, T.; Briquet, Maryline ULg et al

in Astronomy and Astrophysics (2009), 505

Context: The influence of binarity on the late stages of stellar evolution remains an open issue. <BR />Aims: While the first binary post-AGB stars were serendipitously discovered, the distinct ... [more ▼]

Context: The influence of binarity on the late stages of stellar evolution remains an open issue. <BR />Aims: While the first binary post-AGB stars were serendipitously discovered, the distinct characteristics of their spectral energy distribution (SED) allowed us to launch a more systematic search for binaries. We selected post-AGB objects, which exhibit a broad dust excess starting either at H or K, pointing to the presence of a gravitationally bound dusty disc in the system. We initiated an extensive multiwavelength study of those systems and here report on our radial velocity and photometric monitoring results for six stars of early F type, which are pulsators of small amplitude. <BR />Methods: To determine the radial velocity of low signal-to-noise ratio time-series data, we constructed dedicated autocorrelation masks based on high signal-to-noise ratio spectra, used in our published chemical studies. The radial velocity variations were analysed in detail to differentiate between pulsational variability and variability caused by orbital motion. When available, the photometric monitoring data were used to complement the time series of radial velocity data and to establish the nature of the pulsation. Finally, orbital minimalisation was performed to constrain the orbital elements. <BR />Results: All of the six objects are binaries with orbital periods ranging from 120 to 1800 days. Five systems have non-circular orbits. The mass functions range from 0.004 to 0.57 M[SUB]&sun;[/SUB] and the companions are probably unevolved objects of (very) low initial mass. We argue that these binaries must have evolved through a phase of strong binary interaction when the primary was a cool supergiant. Although the origin of the circumstellar disc is not well understood, the disc is generally believed to have formed during this strong interaction phase. The eccentric orbits of these highly evolved objects remain poorly understood. In one object, the line-of-sight grazes the edge of the puffed-up inner rim of the disc. <BR />Conclusions: These results corroborate our earlier statement that evolved objects in binary stars create a Keplerian dusty circumbinary disc. With the measured orbits and mass functions, we conclude that the circumbinary discs seem to have a major impact on the evolution of a significant fraction of binary systems. based on observations collected with the Flemish 1.2 m Mercator telescope at Roque de los Muchachos (Spain), the Swiss 1.2 m Euler telescope at La Silla (Chile) and the 0.5 m and 0.75 m telescopes at SAAO (South-Africa). Tables [see full textsee full text]-[see full textsee full text] are only available in electronic form at http://www.aanda.org Postdoctoral fellow of the Fund for Scientific Research, Flanders. Ph.D. student of the Fund for Scientific Research, Flanders. [less ▲]

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See detailNoise properties of the CoRoT data. A planet-finding perspective
Aigrain, S.; Pont, F.; Fressin, F. et al

in Astronomy and Astrophysics (2009), 506

In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet-finding channel, with a particular emphasis on the time scales characteristic ... [more ▼]

In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet-finding channel, with a particular emphasis on the time scales characteristic of planetary transits. Together with other articles in the same issue of this journal, it forms an attempt to provide the building blocks for a statistical interpretation of the CoRoT planet and eclipsing binary catch to date. After pre-processing the light curves so as to minimise long-term variations and outliers, we measure the scatter of the light curves in the first three CoRoT runs lasting more than 1 month, using an iterative non-linear filter to isolate signal on the time scales of interest. The behaviour of the noise on 2 h time scales is described well by a power-law with index 0.25 in R-magnitude, ranging from 0.1 mmag at R=11.5 to 1 mmag at R=16, which is close to the pre-launch specification, though still a factor 2-3 above the photon noise due to residual jitter noise and hot pixel events. There is evidence of slight degradation in the performance over time. We find clear evidence of enhanced variability on hour time scales (at the level of 0.5 mmag) in stars identified as likely giants from their R magnitude and B-V colour, which represent approximately 60 and 20% of the observed population in the directions of Aquila and Monoceros, respectively. On the other hand, median correlated noise levels over 2 h for dwarf stars are extremely low, reaching 0.05 mmag at the bright end. The CoRoT space mission, launched on December 27, 2006, has been developed and is operated by the CNES, with the contribution of Austria, Belgium, Brazil, ESA, Germany, and Spain. CoRoT data become publicly available one year after release to the Co-Is of the mission from the CoRoT archive: http://idoc-corot.ias.u-psud.fr/. [less ▲]

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See detailPlanetary transit candidates in Corot-IRa01 field
Carpano, S.; Cabrera, J.; Alonso, R. et al

in Astronomy and Astrophysics (2009), 506

Context: CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. <BR />Aims: We present the list of planetary transit ... [more ▼]

Context: CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. <BR />Aims: We present the list of planetary transit candidates detected in the first field observed by CoRoT, IRa01, the initial run toward the Galactic anticenter, which lasted for 60 days. <BR />Methods: We analysed 3898 sources in the coloured bands and 5974 in the monochromatic band. Instrumental noise and stellar variability were taken into account using detrending tools before applying various transit search algorithms. <BR />Results: Fifty sources were classified as planetary transit candidates and the most reliable 40 detections were declared targets for follow-up ground-based observations. Two of these targets have so far been confirmed as planets, CoRoT-1b and CoRoT-4b, for which a complete characterization and specific studies were performed. The CoRoTâ space mission, launched on December 27th 2006, has been developed and is operated by CNES, with contributions from Austria, Belgium, Brazil, ESA, Germany, and Spain. Four French laboratories associated with the CNRS (LESIA, LAM, IAS ,OMP) collaborate with CNES on the satellite development. First CoRoT data are available to the public from the CoRoT archive: http://idoc-corot.ias.u-psud.fr. [less ▲]

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See detailThe secondary eclipse of CoRoT-1b
Alonso, R.; Alapini, A.; Aigrain, S. et al

in Astronomy and Astrophysics (2009), 506

The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the ... [more ▼]

The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response function goes from ~400 to ~1000 nm. We used two different filtering approaches, and several methods to evaluate the significance of a detection of the secondary eclipse. We detect a secondary eclipse centered within 20 min at the expected times for a circular orbit, with a depth of 0.016 ± 0.006%. The center of the eclipse is translated in a 1-Ï upper limit to the planet's eccentricity of e cosÏ < 0.014. Under the assumption of a zero Bond Albedo and blackbody emission from the planet, it corresponds to a T_CoRoT = 2330[SUP]+120[/SUP][SUB]-140[/SUB] K. We provide the equilibrium temperatures of the planet as a function of the amount of reflected light. If the planet is in thermal equilibrium with the incident flux from the star, our results imply an inefficient transport mechanism of the flux from the day to the night sides. Based on observations obtained with CoRoT, a space project operated by the French Space Agency, CNES, with participation of the Science Programme of ESA, ESTEC/RSSD, Austria, Belgium, Brazil, Germany and Spain. [less ▲]

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See detailUn phénomène de double négation : οὐ μή suivis du futur ou du subjonctif
Denizot, Camille ULg

in Syntaktika (2009), 38

La double négation οὐ μή s’emploie devant un subjonctif pour une forte dénégation et devant un futur, dans une interrogation, pour une prohibition. Les éditions hésitent parfois entre les deux expressions ... [more ▼]

La double négation οὐ μή s’emploie devant un subjonctif pour une forte dénégation et devant un futur, dans une interrogation, pour une prohibition. Les éditions hésitent parfois entre les deux expressions, notamment en raison de la proximité morphologique du subjonctif et du futur. À partir d’un examen exhaustif des occurrences chez les trois Tragiques, Aristophane et Platon, on peut montrer que les deux tournures sont sémantiquement et syntaxiquement différentes, particulièrement en ce qui concerne le fonctionnement et la portée des deux négations dans ces deux expressions. [less ▲]

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See detailVariations in sound production in <i>Dascyllus flavicaudus<i>
Kever, Loïc ULg; Lecchini, David; Parmentier, Eric ULg

Poster (2009, October)

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See detailComparaison de 5 techniques de prération du PRP (Platelet-Rich Plasma ou plasma)
Kaux, Jean-François ULg; Le Goff, Caroline ULg; Seidel, Laurence ULg et al

in Annales de Réadaptation et de Médecine Physique (2009, October), 52(Sup. 1), 109

Introduction : Depuis une vingtaine d’années, le développement des activités sportives s’accompagne d’une incidence accrue de diverses tendinopathies, souvent rebelles aux traitements conservateurs ... [more ▼]

Introduction : Depuis une vingtaine d’années, le développement des activités sportives s’accompagne d’une incidence accrue de diverses tendinopathies, souvent rebelles aux traitements conservateurs classiques (anti-inflammatoires non stéroïdiens, orthèses, kinésithérapie, infiltrations…). De nouvelles thérapeutiques, dont l’injection de concentrés plaquettaires (plasma riche en plaquettes ou PRP), sont actuellement en cours d’évaluation clinique. Objectifs : L’injection de PRP fait actuellement l’objet de recherche comme thérapeutique des tendinopathies chroniques. L’injection intra-tendineuse nécessite idéalement un volume minimal afin de diminuer la pression lors de l’injection et minimiser les douleurs, mais il doit également présenter une concentration plaquettaire élevée ; par ailleurs, la quantité de facteurs de croissance libérés pourrait être liée au système de préparation. Méthodes : Après avoir prélevés divers échantillons de sang veineux chez 5 patients, nous avons comparé 5 techniques de préparation du PRP : celle du Service d’Hématologie Biologique du CHU de Liège, le PRP Kit de Curasan®, les techniques Plateltex®, GPS®II et RegenLab®. Résultats : Les différentes techniques permettent d’obtenir des concentrations plaquettaires plus importantes que dans le sang avec des volumes variables (de 0,3 mL à 6 mL) et un nombre de globules rouges et globules blancs limité (sauf pour GPS® II). Le nombre de plaquettes/µL apparaît plus élevé avec la technique Plateltex® et obtient le plus petit volume à injecter. Les autres techniques permettent également d’obtenir de petits volumes sauf avec le GPS®II. Le nombre de plaquettes collectées dans le PRP apparaît donc plus élevé avec cette technique mais avec une concentration faible. Discussion – Conclusion : La technique décrite par Plateltex® permet de recueillir le PRP le plus concentré dans le volume le plus faible. [less ▲]

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See detailLe sociologue dans l'action collective face au risque
Mormont, Marc ULg

in Développement Durable et Territoires [= DDT] (2009)

Modern societies have organised complex systems to tackle with them. Environmental problems progressively reveal new risks that are said modern risks because they can be dealt with through usual systems ... [more ▼]

Modern societies have organised complex systems to tackle with them. Environmental problems progressively reveal new risks that are said modern risks because they can be dealt with through usual systems of risk assessment and management. If some authorities still deny these risks, it is important to observe new dynamics that are here described as capture of fear and that are giving strong power to those who are able to propose control systems. These systems can be destructive of many original and creative practices. Sociologist can not be confined in analysis of risk perception, he has to be involved in collective action that try to deal with risks by confronting different collectives and by reorganising them while preserving autonomy. [less ▲]

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