Results: The 90% confidence intervals for the distance, semi-major axis, and period of the planet are 3.5 kpc < D[SUB]L[/SUB] < 7.9 kpc, 1.1 AU < a < 2.7 AU, and 3.8 yr < P < 7.6 yr, respectively. Photometric data is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/529/A102 [less ▲]Detailed reference viewed: 30 (3 ULg) Transiting planetary system WASP-2 (Southworth+, 2010)Southworth, J.; Mancini, L.; Calchi Novati, S. et alTextual, factual or bibliographical database (2011)Light curves of four transits of the extrasolar planetary system WASP-2 are presented, obtained with substantial telescope defocussing in order to improve the photometric precision of the observations ... [more ▼]Light curves of four transits of the extrasolar planetary system WASP-2 are presented, obtained with substantial telescope defocussing in order to improve the photometric precision of the observations. Three of the datasets were obtained using the Danish 1.5m telescope, DFOSC camera and R filter at ESO La Silla in 2010. One of these datasets was affected by cloud, so was not included in our analysis but is archived with the rest of the data in case it is useful to others. The fourth dataset was obtained with the Loiano 1.52m telescope, BFOSC camera and a Gunn r filter. We also include a datafile containing the times of transit midpoint from our own data and from other sources. [less ▲]Detailed reference viewed: 40 (10 ULg) The International Liquid Mirror Telescope (ILMT) as a Variability Time MachinePoels, Joël ; Borra, Ermanno; Hickson, Paul et alin Griffin, Elisabeth (Ed.) New Horizons In Time-Domain Astronomy, IAU Symposium No. 285, 2011 (2011)During the year 2012 the International Liquid Mirror Telescope (a collaboration between astronomical institutions in Belgium, Canada, India and Poland) will see first light. The instrument will provide ... [more ▼]During the year 2012 the International Liquid Mirror Telescope (a collaboration between astronomical institutions in Belgium, Canada, India and Poland) will see first light. The instrument will provide substantial, in-depth sky coverage and make an unprecedented number of nightly observations. [less ▲]Detailed reference viewed: 47 (14 ULg) Flux and color variations of the quadruply imaged quasar HE 0435--1223Ricci, Davide ; Poels, Joël ; Elyiv, Andrii et alin Astronomy and Astrophysics (2011), 528We present VRi photometric observations of the quadruply imaged quasar HE 0435-1223, carried out with the Danish 1.54m telescope at the La Silla Observatory. Our aim was to monitor and study the ... [more ▼]We present VRi photometric observations of the quadruply imaged quasar HE 0435-1223, carried out with the Danish 1.54m telescope at the La Silla Observatory. Our aim was to monitor and study the magnitudes and colors of each lensed component as a function of time. methods: We monitored the object during two seasons (2008 and 2009) in the VRi spectral bands, and reduced the data with two independent techniques: difference imaging and PSF (Point Spread Function) fitting.results: Between these two seasons, our results show an evident decrease in flux by ~0.2-0.4 magnitudes of the four lensed components in the three filters. We also found a significant increase (~0.05-0.015) in their V-R and R-i color indices. conclusions: These flux and color variations are very likely caused by intrinsic variations of the quasar between the observed epochs. Microlensing effects probably also affect the brightest "A" lensed component. [less ▲]Detailed reference viewed: 82 (17 ULg) HE 0435-1223 lensed QSO VRi light curves (Ricci+, 2011)Ricci, Davide ; Poels, Joël ; Elyiv, Andrii et alTextual, factual or bibliographical database (2011)We present VRi photometric observations of the quadruply imaged quasar HE0435-1223, carried out with the Danish 1.54m telescope at the La Silla Observatory. Our aim was to monitor and study the magnitudes ... [more ▼]We present VRi photometric observations of the quadruply imaged quasar HE0435-1223, carried out with the Danish 1.54m telescope at the La Silla Observatory. Our aim was to monitor and study the magnitudes and colors of each lensed component as a function of time. [less ▲]Detailed reference viewed: 85 (29 ULg) A sub-Saturn Mass Planet, MOA-2009-BLG-319LbMiyake, N.; Sumi, T.; Dong, Subo et alin Astrophysical Journal (2011), 1010We report the gravitational microlensing discovery of a sub-Saturn mass planet, MOA-2009-BLG-319Lb, orbiting a K or M-dwarf star in the inner Galactic disk or Galactic bulge. The high cadence observations ... [more ▼]We report the gravitational microlensing discovery of a sub-Saturn mass planet, MOA-2009-BLG-319Lb, orbiting a K or M-dwarf star in the inner Galactic disk or Galactic bulge. The high cadence observations of the MOA-II survey discovered this microlensing event and enabled its identification as a high magnification event approximately 24 hours prior to peak magnification. As a result, the planetary signal at the peak of this light curve was observed by 20 different telescopes, which is the largest number of telescopes to contribute to a planetary discovery to date. The microlensing model for this event indicates a planet-star mass ratio of q = (3.95 +/- 0.02) x 10^{-4} and a separation of d = 0.97537 +/- 0.00007 in units of the Einstein radius. A Bayesian analysis based on the measured Einstein radius crossing time, t_E, and angular Einstein radius, \theta_E, along with a standard Galactic model indicates a host star mass of M_L = 0.38^{+0.34}_{-0.18} M_{Sun} and a planet mass of M_p = 50^{+44}_{-24} M_{Earth}, which is half the mass of Saturn. This analysis also yields a planet-star three-dimensional separation of a = 2.4^{+1.2}_{-0.6} AU and a distance to the planetary system of D_L = 6.1^{+1.1}_{-1.2} kpc. This separation is ~ 2 times the distance of the snow line, a separation similar to most of the other planets discovered by microlensing. [less ▲]Detailed reference viewed: 36 (6 ULg) A much lower density for the transiting extrasolar planet WASP-7.Southworth, J.; Dominik, M.; Jorgensen, U~G et alTextual, factual or bibliographical database (2011)Detailed reference viewed: 26 (9 ULg) A much lower density for the transiting extrasolar planet WASP-7 (Research Note)Southworth, J.; Dominik, M.; Jorgensen, U~G et alin Astronomy and Astrophysics (2011), 527We present the first high-precision photometry of the transiting extrasolar planetary system WASP-7, obtained using telescope defocussing techniques and reaching a scatter of 0.68 mmag per point. We find ... [more ▼]We present the first high-precision photometry of the transiting extrasolar planetary system WASP-7, obtained using telescope defocussing techniques and reaching a scatter of 0.68 mmag per point. We find that the transit depth is greater and that the host star is more evolved than previously thought. The planet has a significantly larger radius (1.330 +/- 0.093 Rjup versus 0.915 +0.046 -0.040 Rjup) and much lower density (0.41 +/- 0.10 rhojup versus 1.26 +0.25 -0.21 rhojup) and surface gravity (13.4 +/- 2.6 m/s2 versus 26.4 +4.4 -4.0 m/s2) than previous measurements showed. Based on the revised properties it is no longer an outlier in planetary mass--radius and period--gravity diagrams. We also obtain a more precise transit ephemeris for the WASP-7 system. [less ▲]Detailed reference viewed: 25 (11 ULg) 13ème Cours de Mécanique Analytique II (2010-11), Bac3 math & phys fichier pdf+vidéos (mov, avi)Surdej, Jean Learning material (2010)Detailed reference viewed: 157 (18 ULg) 12ème Cours de Mécanique Analytique II (2010-11), Bac3 math & phys fichier pdf+vidéos (mov, avi)Surdej, Jean Learning material (2010)Detailed reference viewed: 192 (28 ULg) 9ème Cours de Mécanique Analytique II (2010-11), Bac3 math & phys fichier pdf+vidéos (mov, avi)Surdej, Jean Learning material (2010)Detailed reference viewed: 187 (26 ULg) ERRATUM: "Physical Properties of the 0.94 Day Period Transiting Planetary System WASP-18" (2009, ApJ, 707, 167)Southworth, John; Hinse, T. C.; Dominik, M. et alin Astrophysical Journal (2010), 723(2), 1829Detailed reference viewed: 43 (11 ULg) High-precision photometry by telescope defocusing - III. The transiting planetary system WASP-2 starSouthworth, John; Mancini, L.; Novati, S Calchi et alin Monthly Notices of the Royal Astronomical Society (2010), 408ABSTRACT We present high-precision photometry of three transits of the extrasolar planetary system WASP-2, obtained by defocusing the telescopes, and achieving scatters of between 0.42 and 0.73 mmag ... [more ▼]ABSTRACT We present high-precision photometry of three transits of the extrasolar planetary system WASP-2, obtained by defocusing the telescopes, and achieving scatters of between 0.42 and 0.73 mmag versus the best-fitting model. These data are modelled using the JKTEBOP code, and taking into account the light from the recently discovered faint star close to the system. The physical properties of the WASP-2 system are derived using tabulated predictions from five different sets of stellar evolutionary models, allowing both statistical and systematic error bars to be specified. We find the mass and radius of the planet to be M[SUB]b[/SUB] = 0.846 +/- 0.055 +/- 0.023M[SUB]Jup[/SUB] and R[SUB]b[/SUB] = 1.043 +/- 0.029 +/- 0.015R[SUB]Jup[/SUB]. It has a low equilibrium temperature of 1281 +/- 21K, in agreement with a recent finding that it does not have an atmospheric temperature inversion. The first of our transit data sets has a scatter of only 0.42mmag with respect to the best-fitting light-curve model, which to our knowledge is a record for ground-based observations of a transiting extrasolar planetary system. Based on data collected by MiNDSTEp with the Danish 1.54-m telescope at the ESO La Silla Observatory. E-mail: jkt@astro.keele.ac.uk ‡ Royal Society University Research Fellow. [less ▲]Detailed reference viewed: 39 (10 ULg) OGLE-2009-BLG-092/MOA-2009-BLG-137: A Dramatic Repeating Event with the Second Perturbation Predicted by Real-time AnalysisRyu, Y*-H; Han, C.; Hwang, K*-H et alin Astrophysical Journal (2010), 723(1), 81-88We report the result of the analysis of a dramatic repeating gravitational microlensing event OGLE-2009-BLG-092/MOA-2009-BLG-137, for which the light curve is characterized by two distinct peaks with ... [more ▼]We report the result of the analysis of a dramatic repeating gravitational microlensing event OGLE-2009-BLG-092/MOA-2009-BLG-137, for which the light curve is characterized by two distinct peaks with perturbations near both peaks. We find that the event is produced by the passage of the source trajectory over the central perturbation regions associated with the individual components of a wide-separation binary. The event is special in the sense that the second perturbation, occurring ~100 days after the first, was predicted by the real-time analysis conducted after the first peak, demonstrating that real-time modeling can be routinely done for binary and planetary events. With the data obtained from follow-up observations covering the second peak, we are able to uniquely determine the physical parameters of the lens system. We find that the event occurred on a bulge clump giant and it was produced by a binary lens composed of a K- and M-type main-sequence stars. The estimated masses of the binary components are M [SUB]1[/SUB] = 0.69 ± 0.11 M [SUB]sun[/SUB] and M [SUB]2[/SUB] = 0.36 ± 0.06 M [SUB]sun[/SUB], respectively, and they are separated in projection by r [SUB]bottom[/SUB] = 10.9 ± 1.3 AU. The measured distance to the lens is D [SUB]L[/SUB] = 5.6 ± 0.7 kpc. We also detect the orbital motion of the lens system. [less ▲]Detailed reference viewed: 50 (8 ULg) 8ème Cours de Mécanique Analytique II (2010-11), Bac3 math & phys fichier pdf+vidéos (mov, avi)Surdej, Jean Learning material (2010)Detailed reference viewed: 158 (26 ULg) First manufactured diamond AGPM vector vortex for the L- and N-bands: metrology and expected performancesDelacroix, Christian ; Forsberg, Pontus; Karlsson, Mikael et alConference (2010, October 28)The AGPM (Annular Groove Phase Mask, Mawet et al. 2005) is an optical vectorial vortex coronagraph (or vector vortex) synthesized by a circular subwavelength grating, that is a grating with a period ... [more ▼]The AGPM (Annular Groove Phase Mask, Mawet et al. 2005) is an optical vectorial vortex coronagraph (or vector vortex) synthesized by a circular subwavelength grating, that is a grating with a period smaller than λ/n (λ being the observed wavelength and n the refractive index of the grating substrate). Since it is a phase mask, it allows to reach a high contrast with a small working angle. Moreover, its subwavelength structure provides a good achromatization over wide spectral bands. Recently, we have manufactured and measured our first N-band prototypes that allowed us to validate the reproducibility of the microfabrication process. Here, we present newly produced mid-IR diamond AGPMs in the N-band (~10 µm), and in the most wanted L-band (~3.5 µm). We first give an extrapolation of the expected coronagraph performances. We then present the manufacturing and measurement results, using diamond-optimized microfabrication techniques such as nano-imprint lithography (NIL) and reactive ion etching (RIE). Finally, the subwavelength grating profile metrology combines surface metrology (scanning electron microscopy, atomic force microscopy, white light interferometry) with diffractometry on an optical polarimetric bench and cross correlation with theoretical simulations using rigorous coupled wave analysis (RCWA). [less ▲]Detailed reference viewed: 65 (15 ULg) Extra-solar planet imaging: ground vs space based coronagraphsHanot, Charles ; Absil, Olivier ; Boccaletti, A. et alConference (2010, October 28)In the context of exoplanet detection, a large majority of the 400 detected exoplanets have been found by indirect methods. Today, progress in the field of high contrast and angular resolution imaging has ... [more ▼]In the context of exoplanet detection, a large majority of the 400 detected exoplanets have been found by indirect methods. Today, progress in the field of high contrast and angular resolution imaging has allowed direct images of several exoplanetary systems to be taken (cf. HR 8799, Fomalhaut and β Pic). In the near future, several new instruments are going to dramatically improve our sensitivity to exoplanet detection. Among these, SPHERE (Spectro Polarimetric High contrast Exoplanet REsearch) at the VLT, MIRI (Mid Infra-Red Instrument) onboard JWST and EPICS at the ELT will be equipped with coronagraphs to reveal faint objects in the vicinity of nearby stars. We made use of the Lyon group (COND) evolutionary models of young (sub-)stellar objects and exoplanets to compare the sensitivities of these different instruments using their estimated coronagraphic profiles. From this comparison, we present a catalogue of targets which are particularly well suited for the different instruments. [less ▲]Detailed reference viewed: 14 (0 ULg) 7ème Cours de Mécanique Analytique II (2010-11), Bac3 math & phys fichier pdf+vidéos (mov, avi)Surdej, Jean Learning material (2010)Detailed reference viewed: 213 (37 ULg) Frequency of Solar-like Systems and of Ice and Gas Giants Beyond the Snow Line from High-magnification Microlensing Events in 2005-2008Gould, A.; Dong, Subo; Gaudi, B. S. et alin Astrophysical Journal (2010), 720We present the first measurement of the planet frequency beyond the "snow line," for the planet-to-star mass-ratio interval –4.5 < log q < –2, corresponding to the range of ice giants to gas giants. We ... [more ▼]We present the first measurement of the planet frequency beyond the "snow line," for the planet-to-star mass-ratio interval –4.5 < log q < –2, corresponding to the range of ice giants to gas giants. We find \endgraf\vbox{\begin{center}$\displaystyle{d^2 N{_{\rm pl}}\over d\log q\, d\log s} = (0.36\pm 0.15)\;{\rm dex}^{-2}$\end{center}}\noindentat the mean mass ratio q = 5 × 10 –4 with no discernible deviation from a flat (Öpik's law) distribution in log-projected separation s. The determination is based on a sample of six planets detected from intensive follow-up observations of high-magnification ( A>200) microlensing events during 2005-2008. The sampled host stars have a typical mass M host ~ 0.5 M sun [less ▲]Detailed reference viewed: 114 (14 ULg)