References of "Surdej, Jean"
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See detailOptical imaging of the gravitational lens system B 1422+231
Remy; Surdej, Jean ULiege; Smette, A. et al

in Astronomy and Astrophysics (1993), 278

Direct optical images (Bessel V, R and Gunn i; average seeing of 0.88 seconds) of B1422+231, obtained in March 1993 at European Southern Observatory (ESO) (La Silla), have been decomposed by fitting ... [more ▼]

Direct optical images (Bessel V, R and Gunn i; average seeing of 0.88 seconds) of B1422+231, obtained in March 1993 at European Southern Observatory (ESO) (La Silla), have been decomposed by fitting multiple Point Spread Functions (PSFs). We detect the optical counterparts of the four known radio point-like components. No additional optical image is found, but due to the compactness of the configuration, our detection limit for additional point sources is rather low (19.3 in R). The deduced positions and photometry of the four optical components agree pretty well with the radio and IR observations and this study provides further evidence supporting the gravitational lens origin of B1422+231. [less ▲]

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See detailThe optical gravitational lens experiment
Surdej, Jean ULiege; Refsdal, S.; Pospieszalska-Surdej, Anna ULiege

in Surdej, Jean; Fraipont-Caro, D.; Gosset, E. (Eds.) et al Proceedings of the 31st Liege International Astrophysical Colloquium (LIAC 93) (1993)

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See detail'Gravitational lenses in the Universe', The proceedings of the 31st Liège International Astrophysical Colloquium
Surdej, Jean ULiege; Fraipont-Caro, D.; Gosset, Eric ULiege et al

Book published by Université de Liège (1993)

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See detailGravitational lensing as a tool: future observational prospects
Surdej, Jean ULiege

Conference (1993)

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See detailESO key programme, gravitational lensing: quasars and radio galaxies; a status report
Surdej, Jean ULiege; Angonin, M. C.; Arnaud, J. et al

in Distribution of Matter in the Universe (1992, December 01)

The scientific background and objectives of our ESO Key Programme are first recalled. A brief account of our research activities (observing runs at ESO and elsewhere, meetings, etc.) is then given ... [more ▼]

The scientific background and objectives of our ESO Key Programme are first recalled. A brief account of our research activities (observing runs at ESO and elsewhere, meetings, etc.) is then given. Preliminary scientific results are presented concerning 1) our observational database for highly luminous quasars and distant powerful radiogalaxies; 2) speckle observations of highly luminous quasars; 3) the photometric monitoring and 4) detailed studies of several known gravitational lenses; 5) optical observations of 3C and 4C radio galaxies and 6) of the well known Einstein ring MG 1131+0456. [less ▲]

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See detailA spectroscopic study of UM 673 A and B - On the size of Lyman-alpha clouds
Smette, A.; Surdej, Jean ULiege; Shaver, P. A. et al

in Astrophysical Journal (1992), 389

The Ly-alpha forest spectra obtained for the A and B images of the gravitationally lensed high-redshift quasar UM 673 are investigated, and higher resolution data of the brightest (A) image are presented ... [more ▼]

The Ly-alpha forest spectra obtained for the A and B images of the gravitationally lensed high-redshift quasar UM 673 are investigated, and higher resolution data of the brightest (A) image are presented. In the 2-A resolution spectra, all the absorption lines detected at 5 sigma in the spectrum of the fainter B image are present in the A image, but two anticoincidences, i.e., two lines in A which do not have a counterpart in B at more than a 3-sigma confidence level, are detected. Given the fact that corresponding Ly-alpha lines in the spectra of A and B have their equivalent widths well correlated, this proves that both light beams actually cross the same clouds. Most of the velocity differences between corresponding lines are compatible with 0 km/s within the error bars, with a standard deviation of 17 km/s. For the two major heavy-element systems detected in the spectrum of UM 673, no significant difference between the corresponding lines in the two spectra are found. [less ▲]

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See detailThe new gravitational lens candidate Q 1208+1011 and the importance of high quality data.
Magain, Pierre ULiege; Surdej, Jean ULiege; Vanderriest, C. et al

in The Messenger (1992), 67

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See detailQ 1208 + 1011 - The most distant imaged quasar, or a binary?
Magain, Pierre ULiege; Surdej, Jean ULiege; Vanderriest, C. et al

in Astronomy and Astrophysics (1992), 253(Letters), 13-16

The paper reports the discovery of a new gravitational lens candidate: the high redshift (z = 3.803) and highly luminous (V = 17.5, M[SUB]V[/SUB] = -30.3) quasar Q 1208 + 1011. As derived from the ... [more ▼]

The paper reports the discovery of a new gravitational lens candidate: the high redshift (z = 3.803) and highly luminous (V = 17.5, M[SUB]V[/SUB] = -30.3) quasar Q 1208 + 1011. As derived from the analysis of direct CCD frames taken with the ESO/MPI 2.2 m telescope, this multiple quasar consists of two pointlike images, separated by 0.45 arcsec and characterized by a brightness ratio of 3.5, in red light. Existing spectroscopic data support the gravitational lens interpretation for this system but cannot exclude the hypothesis of a binary quasar. In the former case, the spectrum suggests that, if the metallic absorption line system reported by Steidel (1990) at a redshift z = 2.9157 is associated with the deflector, the mass of the lens should be of the order of M = 7.8 x 10 exp 11 solar masses. Evaluation of a recent HST PC frame obtained for Q 1208 + 1011 within the snapshot survey for gravitational lenses confirms the above results. [less ▲]

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See detailTables of gravitational lenses
Surdej, Jean ULiege

in Kayser, R.; Schramm, T.; Nieser, L. (Eds.) Gravitational Lenses (1992)

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See detailGravitational lenses: observations, invited talk
Surdej, Jean ULiege

in Proceedings of the First general meeting of the European Astronomical Society "The impact of space research on astronomy" (1992)

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See detailPhotometry, pole orientation and shape parameters of the minor planets 624 Hektor and 43 Ariadne
Detal, Alain ULiege; Collette, P.; Hainaut, O. et al

in Brahic, A.; Gérard, J. C.; Surdej, J. (Eds.) "Observations and physical properties of small solar system bodies", 30th Liège International Astrophysical Colloquium, Institut d’Astrophysique, Liège (1992)

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See detailObservations and physical properties of small solar system bodies
Gérard, Jean-Claude ULiege; Brahic, André; Surdej, Jean ULiege

Book published by Université de Liège (1992)

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See detailUsing the HST archive - gravitational lenses from the snapshot survey
Pirenne, B.; Surdej, Jean ULiege; Magain, Pierre ULiege

Article for general public (1992)

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See detailSearch for gravitational lensing in a sample of highly luminous quasars
Magain, Pierre ULiege; Hutsemekers, Damien ULiege; Surdej, Jean ULiege et al

in Kayser, R.; Schramm, T.; Nieser, L. (Eds.) Proceedings of the Hamburg conference on ’Gravitational Lenses’, Lecture Notes in Physics 406 (1992)

The status of the ESO survey for gravitational lensing among highly luminous quasars (HLQs) is briefly reviewed. The statistics of lensing, both concerning the multiple images and the associations of ... [more ▼]

The status of the ESO survey for gravitational lensing among highly luminous quasars (HLQs) is briefly reviewed. The statistics of lensing, both concerning the multiple images and the associations of galaxies with quasars, are examined. We find a significant overdensity of galaxies very close to the line-of-sight to the HLQs. We also report the discovery of a new multiply lensed quasar candidate. [less ▲]

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See detailGravitational lensing statistics based on a large sample of highly luminous quasars observed with ground-based telescopes and HST
Surdej, Jean ULiege; Claeskens, Jean-François ULiege; Crampton, D. et al

in Benvenuti, Piero; Schreier, Ethan J (Eds.) Proceedings of a ST-ECF/STScI Workshop "Science with the Hubble Space Telescope" (1992)

We present here some recent results on gravitational lensing statistics as applied to a sample of 470 highly luminous quasars.

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See detailOptical observations of gravitational lenses
Surdej, Jean ULiege; Claeskens, Jean-François ULiege; Hutsemekers, Damien ULiege et al

in Kayser, Rainer; Schramm, Thomas; Nieser, Lars (Eds.) Proceedings of the Hamburg conference on ’Gravitational Lenses’, Lecture Notes in Physics 406 (1992)

We report here on some of the major developments achieved on optical observations of gravitational lenses since the last conference devoted to 'Gravitational Lensing'.

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See detailFAS: A new method for deriving the pole orientation and shape parameters of asteroids
Detal, Alain ULiege; Schils, P.; Collette, P. et al

in Gérard, Jean-Claude; Surdej, Jean; Brahic, A. (Eds.) "Observations and physical properties of small solar system bodies", 30th Liège International Astrophysical Colloquium, Institut d’Astrophysique, Liège (1992)

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See detailA Search for Gravitational Lenses Using Sky Survey Plate Scans
Meylan, G.; Djorgovski, S.; Surdej, Jean ULiege et al

in Kayser, Rainer; Schramm, Thomas; Nieser, Lars (Eds.) Proceedings of the Hamburg conference on ’Gravitational Lenses’, Lecture Notes in Physics 406 (1992)

We used scans of sky survey plates available at STScl to look for the presence of multiple-image QSOs which could be due to gravitational lensing. We extracted about 1500 fields, each having 5 arcmin in ... [more ▼]

We used scans of sky survey plates available at STScl to look for the presence of multiple-image QSOs which could be due to gravitational lensing. We extracted about 1500 fields, each having 5 arcmin in size, around QSOs brighter than m v = 18. No lenses have been found so far. We found several cases of galaxies close in projection (within a few arcsec) from QSOs. [less ▲]

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See detailWorld Astronomy Day (WAD) Project #3: Astrophysical and Cosmological Tests Using Gravitational Lenses
Surdej, Jean ULiege; Remy, M.; Haubold, H.

in Benvenuti, P.; Schreier (Eds.) ESO Conference and Workshop Proceedings, No. 44 (1992)

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See detailDeformation of P Cygni line profiles by gravitational microlensing effects
Hutsemekers, Damien ULiege; Surdej, Jean ULiege; Vandrom, E.

in Kayser, R.; Schramm, T.; Nieser, L. (Eds.) Gravitational Lenses, Lecture Notes in Physics, volume 406 (1992)

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