References of "Moreau, O"
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See detailAccurate photometric light curves of the lensed components of Q2237+0305 derived with an optimal image subtraction technique: Evidence for microlensing in image A
Moreau, O.; Libbrecht, C.; Lee, D. W. et al

in Astronomy and Astrophysics (2005), 436(2), 479-492

Using an optimal image subtraction technique, we have derived the V and R light curves of the four lensed QSO components of Q2237+0305 from the monitoring CCD frames obtained by the GLITP collaboration ... [more ▼]

Using an optimal image subtraction technique, we have derived the V and R light curves of the four lensed QSO components of Q2237+0305 from the monitoring CCD frames obtained by the GLITP collaboration with the 2.6m NOT telescope in 1999/2000 (Alcalde et al. 2002). We give here a detailed account of the data reduction and analysis and of the error estimates. In agreement with Wozniak et al. (2000a,b), the good derived photometric accuracy of the GLITP data allows to discuss the possible interpretation of the light curve of component A as due to a microlensing event taking place in the deflecting galaxy. This interpretation is strengthened by the colour dependence of the early rise of the light curve of component A, as it probably corresponds to a caustics crossing by the QSO source. [less ▲]

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See detailQSO 2237+0305 VR light curves from Gravitational Lenses International Time Project optical monitoring
Alcalde, D.; Mediavilla, E.; Moreau, O. et al

in Astrophysical Journal (2002), 572(2, Part 1), 729-734

We present VR observations of QSO 2237+ 0305 conducted by the Gravitational Lensing International Time Project collaboration from 1999 October 1 to 2000 February 3. The observations were made with the 2 ... [more ▼]

We present VR observations of QSO 2237+ 0305 conducted by the Gravitational Lensing International Time Project collaboration from 1999 October 1 to 2000 February 3. The observations were made with the 2.56 m Nordic Optical Telescope at Roque de los Muchachos Observatory, La Palma ( Spain). The pointspread function ( PSF) fitting method and an adapted version of the ISIS subtraction method have been used to derive the VR light curves of the four components ( A D) of the quasar. The mean errors range in the intervals 0.01-0.04 mag ( PSF fitting) and 0.01-0.02 mag ( ISIS subtraction), with the faintest component ( D) having the largest uncertainties. We address the relatively good agreement between the A and D light curves derived using different filters, photometric techniques, and telescopes. The new VR light curves of component A extend the time coverage of a high-magnification microlensing peak, which was discovered by the OGLE team. [less ▲]

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See detailThe 4-m International Liquid Mirror Telescope Project (ILMT) (poster)
Poels, Joël ULg; Borra, E.; Claeskens, Jean-François ULg et al

in Harnden, F. R.; Primini, F. A.; Payne, H. E. (Eds.) Astronomical Data Analysis Software & Systems X Conference (2001)

The working principle of liquid mirror telescopes (LMTs) is first reviewed along with their advantages and disadvantages over classical telescopes. For several reasons (access to regions near the south ... [more ▼]

The working principle of liquid mirror telescopes (LMTs) is first reviewed along with their advantages and disadvantages over classical telescopes. For several reasons (access to regions near the south galactic pole, galactic center, good image quality, etc.), an excellent site for such an LMT is the Atacama desert. A deep (B~24 mag) LMT survey at latitudes near -22deg -- -29deg will cover ~90 square degrees at high galactic latitude and be especially useful for gravitational lensing studies, for the identification of various classes of interesting extragalactic objects (cf. clusters, supernovae, etc. at high redshift) and for subsequent follow-up observations with 8 m-class telescopes. A short description of the handling of data products is also presented. [less ▲]

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See detailSurveys with the 4-m International Liquid Mirror Telescope
Poels, Joël ULg; Moreau, O.; Manfroid, Jean ULg et al

in Mining the Sky (2001)

The working principle of liquid mirror telescopes (LMTs) is first reminded as well as their advantages and disadvantages over classical telescopes. For several obvious reasons (access to regions near the ... [more ▼]

The working principle of liquid mirror telescopes (LMTs) is first reminded as well as their advantages and disadvantages over classical telescopes. For several obvious reasons (access to regions near the south galactic pole, galactic center, good image quality, ...), a best site location for such a LMT is somewhere in the Atacama desert. At latitudes near -22 - -29 degree, a deep (B = 24 mag.) LMT survey will approximately cover 90 square degrees at high galactic latitude, specially useful for gravitational lensing studies, for the identification of various classes of interesting extragalactic objects (cf. clusters, supernovae, etc. at high redshift) and subsequent follow-up observations with 8m-class telescopes. A short description of the handling of data products is also presented. [less ▲]

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See detailSurveys with the 4-m International Liquid Mirror Telescope Project (ILMT) (poster)
Poels, Joël ULg; Moreau, O.; Manfroid, Jean ULg et al

in Banday, A. J.; Zaroubi, S.; Bartelmann, M. (Eds.) Astronomical Data Analysis Software and Systems X (2001)

The working principle of liquid mirror telescopes (LMTs) is first reviewed along with their advantages and disadvantages over classical telescopes. For several reasons (access to regions near the south ... [more ▼]

The working principle of liquid mirror telescopes (LMTs) is first reviewed along with their advantages and disadvantages over classical telescopes. For several reasons (access to regions near the south galactic pole, galactic center, good image quality, etc.), an excellent site for such an LMT is the Atacama desert. A deep (B~24 mag) LMT survey at latitudes near -22deg -- -29deg will cover ~90 square degrees at high galactic latitude and be especially useful for gravitational lensing studies, for the identification of various classes of interesting extragalactic objects (cf. clusters, supernovae, etc. at high redshift) and for subsequent follow-up observations with 8 m-class telescopes. A short description of the handling of data products is also presented. [less ▲]

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See detailDaily monitoring of the gravitational lens QSO 2237+0305 at the Nordic Optical Telescope
Puga, E.; Alcalde, D.; Barrena, R. et al

in Gorgas, Javier; Zamorano, Jaime; Gallego, Jesus (Eds.) Highlights of Spanish astrophysics II (2001)

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See detailSurveys of ultraviolet-excess quasar candidates in large fields
Gosset, Eric ULg; Moreau, O.; Surdej, Jean ULg et al

in Astronomy and Astrophysics. Supplement Series (1997), 123

We describe the results of a survey for moderately bright quasars performed in a 20.6-square-degree field around the galaxy NGC 450. The quasar candidates were selected on the basis of their ultraviolet ... [more ▼]

We describe the results of a survey for moderately bright quasars performed in a 20.6-square-degree field around the galaxy NGC 450. The quasar candidates were selected on the basis of their ultraviolet excess: by comparative visual inspection of the double image of each single object on a U/B dual-exposure Schmidt photographic plate, 95 primary and 45 secondary quasar candidates were selected on the basis of their $U$ image being too bright. The spectroscopic identification of the primary candidates led to the discovery of 59 bona fide quasars (out of which 6 were previously known). The Palomar Schmidt plate was digitised using the MAMA measuring machine and the outcoming data reduced using ad hoc procedures. A photometric calibration allowed us to derive values for the limiting magnitudes and for the U-B index selection threshold of the survey. A catalogue containing 60 quasars is presented with accurate positions, magnitudes and additional information such as redshifts. We studied the spatial distribution of the objects and detected, for the quasars of our sample, a significant deviation from randomness in the form of a propensity to cluster in pairs on the celestial sphere with a typical scale of about 10 arcmin. We also formally detected a tendency towards a 3-D clustering, but this result is induced by a single pair of quasars. A forthcoming paper will deal with a similar work performed in a field around NGC 520; the latter field is located directly to the North of the present one and slightly overlaps it. Based on observations acquired at the Mount Palomar and Las Campanas Observatories as well as at the European Southern Observatory. Also based on Schmidt-plate digitisations performed with the MAMA measuring machine of C.A.I. (I.N.S.U., Paris). [less ▲]

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See detailA Deep Multicolour CCD Survey for Quasar Candidates with the OCA Schmidt Telescope
Moreau, O.; Gosset, Eric ULg; Royer, P. et al

in ASP Conf. Series (1995), 84

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See detailSystematic Search for Quasar Candidates using the MAMA Microdensitometer
Moreau, O.; Gosset, Eric ULg; Reboul, H. et al

in Mc Gillivray, H. T.; Thomson, E. B.; Lasker, B. M. (Eds.) et al Astronomy from wide-field imaging (1994)

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See detailSystematic search for gravitational mirages among general quasar samples
Moreau, O.; Claeskens, Jean-François ULg; Gosset, Eric ULg et al

in Surdej, Jean; Fraipont-Caro, Denise; Gosset, Eric (Eds.) et al The proceedings of the 31st Liège International Astrophysical Colloquium "Gravitational lenses in (1993)

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