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See detailvivre-ensemble (le)
Dawans, Stéphane ULiege

in Durand, Pascal (Ed.) Les nouveaux mots du pouvoir. Abécédaire critique (2007)

Critique d'un terme éthique dont le pouvoir abuse

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See detailVizieR Online Data Catalog: Mixed modes in red giants (Mosser+, 2014)
Mosser, B.; Benomar, O.; Belkacem, K. et al

in VizieR Online Data Catalog (2014), 357

Seismic global parameters of the stars listed in the paper. Each star is identified with its KIC number (Kepler Input Catalog). The asymptotic frequency and period spacing are derived from the fit of the ... [more ▼]

Seismic global parameters of the stars listed in the paper. Each star is identified with its KIC number (Kepler Input Catalog). The asymptotic frequency and period spacing are derived from the fit of the radial and dipole oscillation modes. The stellar mass is derived from the seismic scaling relations. The evolutionary status is derived according to the location of the star in the DPi1 - Dnu diagram (Fig. 1) (1 data file). [less ▲]

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See detailVizieR Online Data Catalog: Planet candidates discovered using K2's 1st yr (Crossfield+, 2016)
Crossfield, I. J. M.; Ciardi, D. R.; Petigura, E. A. et al

in Planet candidates discovered using K2's 1st yr (Crossfield+, 2016) (2016)

We select our FGK stellar sample from the all-sky Transiting Exoplanet Survey Satellite (TESS) Dwarf Catalog (TDC; Stassun et al. 2014, arXiv:1410.6379). We extract time-series photometry from the target ... [more ▼]

We select our FGK stellar sample from the all-sky Transiting Exoplanet Survey Satellite (TESS) Dwarf Catalog (TDC; Stassun et al. 2014, arXiv:1410.6379). We extract time-series photometry from the target pixel files provided by the K2 project using circular, stationary, soft-edged apertures. See section 2 for further explanations. We obtained high-resolution optical spectra of 83 planet candidate hosts using the HIRES echelle spectrometer on the 10m Keck I telescope (R=55000). We obtained spectra of 27 candidate host stars using the Levy high-resolution optical spectrograph mounted at the Automated Planet Finder (APF; R~80000 or 100000). We obtained spectra of a small number of candidate stellar hosts using the FEROS fiber-fed echelle spectrograph at the 2.2m MPG telescope (R~48000). See section 3.1 for further details. We obtained high-resolution imaging (HRI) for 164 of our candidate systems. Our primary instrument for this work was NIRC2 at the 10m Keck II telescope, with which we observed 110 systems. As part of multi-semester program GN-2015B-LP-5 (PI Crossfield) at Gemini Observatory, we observed 40 systems with the NIRI camera in the K-band. We also observed 33 stars with PHARO/PALM-3000 at the 5m Hale Telescope and 14 systems with LMIRCam at LBT, all at the K-band. We observed 39 stars at visible wavelengths using the automated Robo-AO laser adaptive optics system at the Palomar 1.5m telescope. Through our Long-Term Gemini program we also acquired high-resolution speckle imaging of 32 systems in narrowband filters centered at 692 and 880nm using the DSSI camera at the Gemini North telescope. See section 3.3 for further explanations. (7 data files). [less ▲]

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See detailVizieR Online Data Catalog: Polarization of quasars (Hutsemekers+, 2017)
Hutsemekers, Damien ULiege; Hall, P.; Sluse, Dominique ULiege

Textual, factual or bibliographical database (2017)

This Table contains optical linear polarization measurements of 192 quasars obtained in April 2003, April 2007, and October 2007 with the ESO Faint Object Spectrograph and Camera (EFOSC2) instrument ... [more ▼]

This Table contains optical linear polarization measurements of 192 quasars obtained in April 2003, April 2007, and October 2007 with the ESO Faint Object Spectrograph and Camera (EFOSC2) instrument attached to the 3.6m telescope at the La Silla Observatory. (1 data file). [less ▲]

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See detailVizieR Online Data Catalog: Polarization of quasars (Hutsemekers+, 2018)
Hutsemekers, Damien ULiege; Borguet, B.; Sluse, Dominique ULiege et al

Textual, factual or bibliographical database (2018)

This Table contains optical linear polarization measurements of 86 quasars obtained in May 2008, October 2008, and from April to July 2015 with the Focal Reducer and low dispersion Spectrographs FORS1 and ... [more ▼]

This Table contains optical linear polarization measurements of 86 quasars obtained in May 2008, October 2008, and from April to July 2015 with the Focal Reducer and low dispersion Spectrographs FORS1 and FORS2 attached to the Very Large Telescope at the Paranal Observatory. (1 data file). [less ▲]

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See detailVizieR Online Data Catalog: WASP-22, WASP-41, WASP-42, WASP-55 (Southworth+, 2016)
Southworth, J.; Tregloan-Reed, J.; Andersen, M. I. et al

in Monthly Notices of the Royal Astronomical Society (2018), 745

17 light curves of transits of the extrasolar planetary systems WASP-22, WASP-41, WASP-42 and WASP-55 are presented. 13 of the light curves were obtained using the Danish 1.54m telescope at ESO La Silla ... [more ▼]

17 light curves of transits of the extrasolar planetary systems WASP-22, WASP-41, WASP-42 and WASP-55 are presented. 13 of the light curves were obtained using the Danish 1.54m telescope at ESO La Silla, Chile, in the Bessell R or Bessell I passbands. The other 4 light curves were obtained using the 84cm telescope at Observatorio Cerro Armazones, Chile, using either an R filter or no filter. The errorbars for each transit have been scaled so the best-fitting model (obtained using the JKTEBOP code) has a reduced chi-squared value of 1.0. (4 data files). [less ▲]

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See detailVlaams dichterschap
Spinoy, Erik ULiege

in Dietsche Warande en Belfort (1987), 132(5), 69-71

This is a review of a prose work by the Flemish modernist writer Lucienne Stassaert.

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See detailVLT + UVES spectroscopy of the low-ionization intrinsic absorber in SDSS J001130.56+005550.7
Hutsemekers, Damien ULiege; Hall, Patrick; Brinkmann, J.

in Astronomy and Astrophysics (2004), 415

We analyse high-resolution VLT+UVES spectra of the low-ionization intrinsic absorber observed in the BAL QSO SDSS J001130.56+005550.7. Two narrow absorption systems at velocities -600 km s[SUP]-1[/SUP ... [more ▼]

We analyse high-resolution VLT+UVES spectra of the low-ionization intrinsic absorber observed in the BAL QSO SDSS J001130.56+005550.7. Two narrow absorption systems at velocities -600 km s[SUP]-1[/SUP] and -22 000 km s[SUP]-1[/SUP] are detected. The low-velocity system is part of the broad absorption line (BAL), while the high-velocity one is well detached. While most narrow absorption components are only detected in the high-ionization species, the lowest velocity component is detected in both high- and low-ionization species, including in the excited Si II[SUP]*[/SUP] and C II[SUP]*[/SUP] lines. From the analysis of doublet lines, we find that the narrow absorption lines at the low-velocity end of the BAL trough are completely saturated but do not reach zero flux, their profiles being dominated by a velocity-dependent covering factor. The covering factor is significantly smaller for Mg II than for Si IV and N V , which demonstrates the intrinsic nature of absorber. From the analysis of the excited Si II[SUP]*[/SUP] and C II[SUP]*[/SUP] lines in the lowest velocity component, we find an electron density ~=10[SUP]3[/SUP] cm[SUP]-3[/SUP]. Assuming photoionization equilibrium, we derive a distance ~=20 kpc between the low-ionization region and the quasar core. The correspondence in velocity of the high- and low-ionization features suggests that all these species must be closely associated, hence formed at the same distance of Ë 20 kpc, much higher than the distance usually assumed for BAL absorbers. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile (ESO 267.A-5698). [less ▲]

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See detailVLT adaptive optics search for luminous substructures in the lens galaxy towards SDSS J0924+0219
Faure, C.; Sluse, Dominique ULiege; Cantale, N. et al

in Astronomy and Astrophysics (2011), 536

The anomalous flux ratios between quasar images are suspected of being caused by substructures in lens galaxies. We present new deep and high-resolution H and Ks imaging of the strongly lensed quasar SDSS ... [more ▼]

The anomalous flux ratios between quasar images are suspected of being caused by substructures in lens galaxies. We present new deep and high-resolution H and Ks imaging of the strongly lensed quasar SDSS J0924+0219 obtained using the ESO VLT with adaptive optics and the laser guide star system. SDSS J0924+0219 is particularly interesting because the observed flux ratio between the quasar images vastly disagree with the predictions from smooth mass models. With our adaptive optics observations we find a luminous object, Object L, located ~0.3'' to the north of the lens galaxy, but we show that it cannot be responsible for the anomalous flux ratios. Object L as well as a luminous extension of the lens galaxy to the south are seen in the archival HST/ACS image in the F814W filter. This suggests that Object L is part of a bar in the lens galaxy, as also supported by the presence of a significant disk component in the light profile of the lens galaxy. Finally, we find no evidence of any other luminous substructure that may explain the quasar images flux ratios. However, owing to the persistence of the flux ratio anomaly over time (~7 years), a combination of microlensing and millilensing is the favorite explanation for the observations. Based on observations obtained with the ESO VLT at Paranal observatory (Prog ID 084.A-0762(A); PI: Meylan). Also based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with the CASTLES (Cfa-Arizona Space Telescope LEns Survey) survey (ID: 9744, PI: C. S. Kochanek). [less ▲]

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See detailVLT observations of the highly ionized nebula around Brey2
Nazé, Yaël ULiege; Rauw, Grégor ULiege; Manfroid, Jean ULiege et al

in Astronomy and Astrophysics (2003), 401(2), 13-16

We present the first high resolution He II lambda4686 images of the high excitation nebula around the WR star Brey2 in the LMC. This nebula presents a striking morphology: a small arc-like feature some 3 ... [more ▼]

We present the first high resolution He II lambda4686 images of the high excitation nebula around the WR star Brey2 in the LMC. This nebula presents a striking morphology: a small arc-like feature some 3.6 pc in radius is particularly prominent in the He II lambda4686 line. We further discover a previously unknown faint He II emission that extends over an area of 22 x 17 pc(2). An even fainter He II emission is apparently associated with the interstellar bubble blown by the progenitor of Brey2. The total He II flux corresponds to an ionizing flux of 4 x 10(47) photons s(-1). Halpha, [O III], and He I lambda5876 images and long-slit spectra are also examined in this letter, enabling us to investigate the detailed physical properties at various locations of the nebula. [less ▲]

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See detailVLT Observations of two Unusual BAL Quasars
Hall, Patrick; Hutsemekers, Damien ULiege

in Active Galactic Nuclei: From Central Engine to Host Galaxy. ASPC 290 (2003)

The SDSS has confirmed the existence of populations of broad absorption line quasars with extreme properties. I will discuss the discovery of redshifted absorption troughs (confirmation of a rotating disk ... [more ▼]

The SDSS has confirmed the existence of populations of broad absorption line quasars with extreme properties. I will discuss the discovery of redshifted absorption troughs (confirmation of a rotating disk wind?), absorption from FeIII but not FeII (a very large column density of moderately ionized gas?), extremely reddened objects (extinction curves even steeper than that of the SMC), objects with overlapping troughs that remove 90% of the flux below MgII, and two mysterious objects which may or may not be unusual BALs. Implications of these objects for quasar and BAL outflow models will be discussed, along with preliminary results of various followup observations. [less ▲]

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See detailVLT on-axis spectroscopy of quasar host galaxies
Letawe, Géraldine ULiege; Magain, Pierre ULiege; Courbin, F. et al

in New Astronomy Reviews (2005, August), 50(issue 9-10), 779

We present the full analysis of our sample of 20 bright low redshift quasars (M-B < -23 and z < 0.35), observed spectroscopically with the VLT FORS1, with objectives of characterizing the hosts and trying ... [more ▼]

We present the full analysis of our sample of 20 bright low redshift quasars (M-B < -23 and z < 0.35), observed spectroscopically with the VLT FORS1, with objectives of characterizing the hosts and trying to understand how quasars are fueled or triggered. Applying the MCS deconvolution method, we are able to separate the galactic light from the quasar light, enabling i.e. global analysis of the gaseous and stellar content and gaseous dynamics. We find that 45% of the sample show signs of interaction, while half of the quasars are hosted in spiral galaxies, even when brighter than M-V = -23.5. We also find many galaxies containing gas ionized by the quasar radiation far from the nucleus, all of these showing interaction or merger signs. We find spectroscopic evidences that such interactions bring gas in the broad and narrow line regions and power the nucleus. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailVLT transit and occultation photometry for the bloated planet CoRoT-1b
Gillon, Michaël ULiege; Demory, B.-O.; Triaud, A.H.M.J. et al

in Astronomy and Astrophysics (2009), 506

We present VLT eclipse photometry for the giant planet CoRoT-1b. We observed a transit in the R-band filter and an occultation in a narrow filter centered on 2.09 microns. Our analysis of this new ... [more ▼]

We present VLT eclipse photometry for the giant planet CoRoT-1b. We observed a transit in the R-band filter and an occultation in a narrow filter centered on 2.09 microns. Our analysis of this new photometry and published radial velocities, in combination with stellar-evolutionary modeling, leads to a planetary mass and radius of 1.07 (+0.13,-0.18) M_Jup and 1.45 (+0.07,-0.13) R_Jup, confirming the very low density previously deduced from CoRoT photometry. The large occultation depth that we measure at 2.09 microns (0.278 (+0.043,-0.066) %) is consistent with thermal emission and is better reproduced by an atmospheric model with no redistribution of the absorbed stellar flux to the night side of the planet. [less ▲]

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See detailVLT+UVES Spectroscopy of the Ca II Low-Ionization Broad Absorption Line Quasar SDSS J030000.56+004828.0
Hall, Patrick B; Hutsemekers, Damien ULiege; Anderson, Scott F et al

in Astrophysical Journal (2003), 593

We study high-resolution spectra of the ``overlapping-trough'' low-ionization broad absorption line (LoBAL) quasar SDSS J030000.56+004828.0. The Ca II, Mg II, and Mg I column densities in this object are ... [more ▼]

We study high-resolution spectra of the ``overlapping-trough'' low-ionization broad absorption line (LoBAL) quasar SDSS J030000.56+004828.0. The Ca II, Mg II, and Mg I column densities in this object are the largest reported to date for any BAL outflow. The broad Ca II absorption is mildly blended, but the blending can be disentangled to measure the Ca II column density, which is large enough that the outflow must include a strong hydrogen ionization front. The outflow begins at a blueshift of ~1650 km s[SUP]-1[/SUP] from the systemic redshift. The lowest velocity BAL region produces strong Ca II absorption but does not produce significant excited Fe II absorption, while the higher velocity excited Fe II absorption region produces very little Ca II absorption. We have found that only a disk wind outflow can explain this segregation. Whether the outflow is smooth or clumpy, we conclude that the Ca II BAL region has a density high enough to populate excited levels of Fe II but a temperature low enough to prevent them from being significantly populated. This requirement means the Ca II BAL region has T<~1100 K, and perhaps even T<~550 K. This quasar also has an associated absorption line system (AAL) that exhibits partial covering and therefore is likely located near the central engine. Its association with the BAL outflow is unclear. Blending of the AAL with the BAL trough shows that the spatial region covered by the BAL outflow can vary over velocity differences of ~1700 km s[SUP]-1[/SUP]. Based on observations from ESO Director's Discretionary Time program 267.A-5698. [less ▲]

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See detailThe VLT-FLAMES Tarantula Survey. XXIX. Massive star formation in the local 30 Doradus starburst
Schneider, F. R. N.; Ramírez-Agudelo, O. H.; Tramper, F. et al

in Astronomy and Astrophysics (2018), 618

The 30 Doradus (30 Dor) nebula in the Large Magellanic Cloud (LMC) is the brightest HII region in the Local Group and a prototype starburst similar to those found in high redshift galaxies. It is thus a ... [more ▼]

The 30 Doradus (30 Dor) nebula in the Large Magellanic Cloud (LMC) is the brightest HII region in the Local Group and a prototype starburst similar to those found in high redshift galaxies. It is thus a stepping stone to understand the complex formation processes of stars in starburst regions across the Universe. Here, we have studied the formation history of massive stars in 30 Dor using masses and ages derived for 452 mainly OB stars from the spectroscopic VLT-FLAMES Tarantula Survey (VFTS). We find that stars of all ages and masses are scattered throughout 30 Dor. This is remarkable because it implies that massive stars either moved large distances or formed independently over the whole field of view in relative isolation. We find that both channels contribute to the 30 Dor massive star population. Massive star formation rapidly accelerated about 8 Myr ago, first forming stars in the field before giving birth to the stellar populations in NGC 2060 and NGC 2070. The R136 star cluster in NGC 2070 formed last and, since then, about 1 Myr ago, star formation seems to be diminished with some continuing in the surroundings of R136. Massive stars within a projected distance of 8 pc of R136 are not coeval but show an age range of up to 6 Myr. Our mass distributions are well populated up to 200 M[SUB]⊙[/SUB]. The inferred IMF is shallower than a Salpeter-like IMF and appears to be the same across 30 Dor. By comparing our sample of stars to stellar models in the Hertzsprung-Russell diagram, we find evidence for missing physics in the models above log L/L[SUB]⊙[/SUB] = 6 that is likely connected to enhanced wind mass loss for stars approaching the Eddington limit. Our work highlights the key information about the formation, evolution and final fates of massive stars encapsulated in the stellar content of 30 Dor, and sets a new benchmark for theories of massive star formation in giant molecular clouds. Based on observations collected at the European Southern Observatory under programme ID 182.D-0222. [less ▲]

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See detailThe VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs at wide orbits . III. The frequency of brown dwarfs and giant planets as companions to solar-type stars
Reggiani, Maddalena ULiege; Meyer, M. R.; Chauvin, G. et al

in Astronomy and Astrophysics (2016), 586

Context. In recent years there have been many attempts to characterize the occurrence and distribution of stellar, brown dwarf (BD), and planetary-mass companions to solar-type stars with the aim of ... [more ▼]

Context. In recent years there have been many attempts to characterize the occurrence and distribution of stellar, brown dwarf (BD), and planetary-mass companions to solar-type stars with the aim of constraining formation mechanisms. From radial velocity observations a dearth of companions with masses between 10-40 M[SUB]Jupiter[/SUB] has been noticed at close separations, suggesting the possibility of a distinct formation mechanism for objects above and below this range. <BR /> Aims: We present a model for the substellar companion mass function (CMF). This model consists of the superposition of the planet and BD companion mass distributions, assuming that we can extrapolate the radial velocity measured CMF for planets to larger separations and the stellar companion mass-ratio distribution over all separations into the BD mass regime. By using both the results of the VLT/NaCo large program (NaCo-LP) and the complementary archive datasets, which probe the occurrence of planets and BDs on wide orbits around solar-type stars, we place some constraints on the planet and BD distributions. <BR /> Methods: We developed a Monte Carlo simulation tool to predict the outcome of a given survey, depending on the shape of the orbital parameter distributions (mass, semimajor axis, eccentricity, and inclination). Comparing the predictions with the results of the observations, we calculate the likelihood of different models and which models can be ruled out. <BR /> Results: Current observations are consistent with the proposed model for the CMF, as long as a sufficiently small outer truncation radius (≲100 AU) is introduced for the planet separation distribution. Some regions of parameter space can be excluded by the observations. <BR /> Conclusions: We conclude that the results of the direct imaging surveys searching for substellar companions around Sun-like stars are consistent with a combined substellar mass spectrum of planets and BDs. This mass distribution has a minimum between 10 and 50 M[SUB]Jupiter[/SUB], in agreement with radial velocity measurements. In this picture the dearth of objects in this mass range would naturally arise from the shape of the mass distribution, without the introduction of any distinct formation mechanism for BDs. This kind of model for the CMF allows us to determine the probability for a substellar companion as a function of mass to have formed in a disk or from protostellar core fragmentation, as such mechanisms overlap in this mass range. Based on observations collected at the European Southern Observatory, Chile (ESO Large Program 184.C-0157 and Open Time 089.C-0137A and 090.C-0252A). [less ▲]

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See detailThe VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs at wide orbits. II. Survey description, results, and performances
Chauvin, G.; Vigan, A.; Bonnefoy, M. et al

in Astronomy and Astrophysics (2015), 573

Context. Young, nearby stars are ideal targets for direct imaging searches for giant planets and brown dwarf companions. After the first-imaged planet discoveries, vast efforts have been devoted to the ... [more ▼]

Context. Young, nearby stars are ideal targets for direct imaging searches for giant planets and brown dwarf companions. After the first-imaged planet discoveries, vast efforts have been devoted to the statistical analysis of the occurence and orbital distributions of giant planets and brown dwarf companions at wide (≥5-6 AU) orbits. <BR /> Aims: In anticipation of the VLT/SPHERE planet-imager, guaranteed-time programs, we have conducted a preparatory survey of 86 stars between 2009 and 2013 to identify new faint comoving companions to ultimately analyze the occurence of giant planets and brown dwarf companions at wide (10-2000 AU) orbits around young, solar-type stars. <BR /> Methods: We used NaCo at VLT to explore the occurrence rate of giant planets and brown dwarfs between typically 0.1 and 8''. Diffraction-limited observations in H-band combined with angular differential imaging enabled us to reach primary star-companion brightness ratios as small as 10[SUP]-6[/SUP] at 1.5''. Repeated observations at several epochs enabled us to discriminate comoving companions from background objects. <BR /> Results: During our survey, twelve systems were resolved as new binaries, including the discovery of a new white dwarf companion to the star HD 8049. Around 34 stars, at least one companion candidate was detected in the observed field of view. More than 400 faint sources were detected; 90% of them were in four crowded fields. With the exception of HD 8049 B, we did not identify any new comoving companions. The survey also led to spatially resolved images of the thin debris disk around HD 61005 that have been published earlier. Finally, considering the survey detection limits, we derive a preliminary upper limit on the frequency of giant planets for the semi-major axes of [10, 2000] AU: typically less than 15% between 100 and 500 AU and less than 10% between 50 and 500 AU for exoplanets that are more massive than 5 M[SUB]Jup[/SUB] and 10 M[SUB]Jup[/SUB] respectively, if we consider a uniform input distribution and a confidence level of 95%. <BR /> Conclusions: The results from this survey agree with earlier programs emphasizing that massive, gas giant companions on wide orbits around solar-type stars are rare. These results will be part of a broader analysis of a total of ~210 young, solar-type stars to bring further statistical constraints for theoretical models of planetary formation and evolution. Based on observations collected at the European Southern Observatory, Chile (ESO Large Program 184.C-0157 and Open Time 089.C-0137A and 090.C-0252A).Tables 2 and 6 are available in electronic form at <A href="http://www.aanda.org/10.1051/0004-6361/201423564/olm">http://www.aanda.org</A> [less ▲]

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See detailThe VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs at wide orbits. IV. Gravitational instability rarely forms wide, giant planets
Vigan, A.; Bonavita, M.; Biller, B. et al

in Astronomy and Astrophysics (2017), 603

Understanding the formation and evolution of giant planets (≥1 M[SUB]Jup[/SUB]) at wide orbital separation (≥5 AU) is one of the goals of direct imaging. Over the past 15 yr, many surveys have placed ... [more ▼]

Understanding the formation and evolution of giant planets (≥1 M[SUB]Jup[/SUB]) at wide orbital separation (≥5 AU) is one of the goals of direct imaging. Over the past 15 yr, many surveys have placed strong constraints on the occurrence rate of wide-orbit giants, mostly based on non-detections, but very few have tried to make a direct link with planet formation theories. In the present work, we combine the results of our previously published VLT/NaCo large program with the results of 12 past imaging surveys to constitute a statistical sample of 199 FGK stars within 100 pc, including three stars with sub-stellar companions. Using Monte Carlo simulations and assuming linear flat distributions for the mass and semi-major axis of planets, we estimate the sub-stellar companion frequency to be within 0.75-5.70% at the 68% confidence level (CL) within 20-300 AU and 0.5-75 M[SUB]Jup[/SUB], which is compatible with previously published results. We also compare our results with the predictions of state-of-the-art population synthesis models based on the gravitational instability (GI) formation scenario with and without scattering. We estimate that in both the scattered and non-scattered populations, we would be able to detect more than 30% of companions in the 1-75 M[SUB]Jup[/SUB] range (95% CL). With the threesub-stellar detections in our sample, we estimate the fraction of stars that host a planetary system formed by GI to be within 1.0-8.6% (95% CL). We also conclude that even though GI is not common, it predicts a mass distribution of wide-orbit massive companions that is much closer to what is observed than what the core accretion scenario predicts. Finally, we associate the present paper with the release of the Direct Imaging Virtual Archive (DIVA), a public database that aims at gathering the results of past, present, and future direct imaging surveys. Based on observations collected at the European Southern Observatory, Chile (ESO Large Program 184.C-0157 and Open Time 089.C-0137A and 090.C-0252A). [less ▲]

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See detailVLT/SPHERE observations and shape reconstruction of asteroid (6) Hebe
Marsset, Michael; Carry, Benoit; Dumas, Christophe et al

in AAS/Division for Planetary Sciences Meeting Abstracts (2016, October 01)

(6) Hebe is a large main-belt asteroid, accounting for about half a percent of the mass of the asteroid belt. Its spectral characteristics and close proximity to dynamical resonances within the main-belt ... [more ▼]

(6) Hebe is a large main-belt asteroid, accounting for about half a percent of the mass of the asteroid belt. Its spectral characteristics and close proximity to dynamical resonances within the main-belt (the 3:1 Kirkwood gap and the nu6 resonance) make it a probable parent body of the H-chondrites and IIE iron meteorites found on Earth.We present new AO images of Hebe obtained with the high-contrast imager SPHERE (Beuzit et al. 2008) as part of the science verification of the instrument. Hebe was observed close to its opposition date and throughout its rotation in order to derive its 3-D shape, and to allow a study of its surface craters. Our observations reveal impact zones that witness a severe collisional disruption for this asteroid. When combined to previous AO images and available lightcurves (both from the literature and from recent optical observations by our team), these new observations allow us to derive a reliable shape model using our KOALA algorithm (Carry et al. 2010). We further derive an estimate of Hebe's density based on its known astrometric mass. [less ▲]

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