Eigenbrod, A., Courbin, F., Meylan, G., Agol, E., Anguita, T., Schmidt, R. W., ...
We present the continuation of our long-term spectroscopic monitoring of the gravitationally lensed quasar QSO 2237+0305. We investigate the chromatic variations observed in the UV/optical continuum...
Sluse, D., Courbin, F., Eigenbrod, A., Meylan, G.
We present the first VLT near-IR observations of a gravitationally lensed quasar, using Adaptive Optics and Laser Guide Stars. These observations can be considered as a test bench for future...
Microlensing to probe the quasar structure: spectrophotometry of Q2237+0305 and of J1131-1231 (2008)
Sluse, D., Eigenbrod, A., Courbin, F., Hutsemékers, D., Meylan, G., ...
We present the main results of the first long-term spectrophotometric monitoring of the ``Einstein cross'' Q2237+0305 and of the single-epoch spectra of the lensed quasar J1131-1231. From October...
Microlensing variability in the gravitationally lensed quasar Q2237+0305 = the Einstein Cross (2008)
Eigenbrod, A., Courbin, F., Sluse, D., Meylan, G., Agol, E.
We present the results of the first long-term (2.2 years) spectroscopic monitoring of a gravitationally lensed quasar, namely the Einstein Cross Q2237+0305. We spatially deconvolve deep VLT/FORS1...
Vuissoz, C., Courbin, F., Sluse, D., Meylan, G., Chantry, V., Eulaers, E., ...
Gravitationally lensed quasars can be used to map the mass distribution in lensing galaxies and to estimate the Hubble constant H0 by measuring the time delays between the quasar images. Here we...
Courbin, F., North, P., Eigenbrod, A., Chelouche, D.
We report the first results of a spectroscopic search for Lyman alpha, envelopes around three z=4.5 radio-quiet quasars. Our observational strategy uses the FORS2 spectrograph attached to the UT1 of...
Letawe, Y., Magain, P., Letawe, G., Courbin, F., Hutsemékers, D.
The host galaxies of six nearby QSOs are studied on the basis of high resolution HST optical images and spatially resolved VLT slit spectra. The gas ionization and velocity are mapped as a function...
Simultaneous Estimation of Time Delays and Quasar Structure (2007)
Morgan, Christopher W., Eyler, Michael E., Kochanek, C. S., Morgan, Nicholas D., Falco, Emilio E., Vuissoz, Christel, ...
We expand our Bayesian Monte Carlo method for analyzing the light curves of gravitationally lensed quasars to simultaneously estimate time delays and quasar structure including their mutual...
Slit and integral-field optical spectroscopy of the enigmatic quasar HE0450-2958 (2007)
Letawe, G., Magain, P., Courbin, F.
Interest in the quasar HE0450-2958 arose following the publication of the non-detection of its expected massive host, leading to various interpretations. This article investigates the gaseous and...
Eigenbrod, A., Courbin, F., Sluse, D., Meylan, G., Agol, E.
We present the results of the first long-term (2.2 years) spectroscopic monitoring of a gravitationally lensed quasar, namely the Einstein Cross Q2237+0305. The goal of this paper is to present the...
Willis, J. P., Courbin, F., Kneib, J. P., Minniti, D.
We present the results of a continuing survey to detect Lya emitting galaxies at redshifts z~9: the ZEN ("z equals nine'') survey. We have obtained deep VLT/ISAAC observations in the narrow J-band...
Discovery of a Probable Physical Triple Quasar (2007)
Djorgovski, S. G., Courbin, F., Meylan, G., Sluse, D., Thompson, D. J., Mahabal, A., ...
We report the discovery of the first known probable case of a physical triple quasar (not a gravitational lens). A previously known double system, QQ 1429-008 at z = 2.076, is shown to contain a...
On-axis spectroscopy of the host galaxies of 20 optically luminous quasars at z ~ 0.3 (2007)
Letawe, G., Magain, P., Courbin, F., Jablonka, P., Jahnke, K., Meylan, G., ...
We present the analysis of a sample of 20 bright low-redshift quasars (MB < -23 and z < 0.35) observed spectroscopically with the Very Large Telescope (VLT). The Focal Reducer/low dispersion...
Spatial decomposition of on-nucleus spectra of quasar host galaxies (2007)
Jahnke, K., Wisotzki, L., Courbin, F., Letawe, G.
In order to study the host galaxies of type 1 (broad-line) quasars, we present a semi-analytic modelling method to decompose the on-nucleus spectra of quasars into nuclear and host galaxy channels....
Eigenbrod, A., Courbin, F., Meylan, G.
Aims: The knowledge of the redshift of a lensing galaxy that produces multiple images of a background quasar is essential to any subsequent modeling, whether related to the determination of the...
Magain, P., Courbin, F., Gillon, M., Sohy, S., Letawe, G., Chantry, V., ...
A new method is presented for determining the Point Spread Function (PSF) of images that lack bright and isolated stars. It is based on the same principles as the MCS (Magain, Courbin, Sohy, 1998)...
Gillon, M., Pont, F., Moutou, C., Bouchy, F., Courbin, F., Sohy, S., ...
A high accuracy photometry algorithm is needed to take full advantage of the potential of the transit method for the characterization of exoplanets, especially in deep crowded fields. It has to...
Gillon, M., Pont, F., Moutou, C., Bouchy, F., Courbin, F., Sohy, S., ...
A high accuracy photometry algorithm is needed to take full advantage of the potential of the transit method for the characterization of exoplanets, especially in deep crowded fields. It has to...
Vuissoz, C., Courbin, F., Sluse, D., Meylan, G., Ibrahimov, M., Asfandiyarov, I., ...
Aims: Our aim is to measure the time delay between the two gravitationally lensed images of the z = 1.547 quasar SDSS J1650+4251, in order to estimate the Hubble constant H_0. Methods: Our...
On-axis spectroscopy of the host galaxies of 20 optically luminous quasars at z~0.3 (2006)
Letawe, G., Magain, P., Courbin, F., Jablonka, P., Jahnke, K., Meylan, G., ...
We present the analysis of a sample of 20 bright low-redshift quasars (M_B
ZEN and the search for high-redshift galaxies (2006)
Willis, J. P., Courbin, F., Kneib, J-P., Minniti, D.
We present the ZEN (z equals nine) survey: a deep, narrow J-band search for proto-galactic Lya emission at redshifts z=9. In the first phase of the survey, dubbed ZEN1, we combine an exceptionally...
Saha, P., Courbin, F., Sluse, D., Dye, S., Meylan, G.
Aims: To predict time delays for a sample of gravitationally lensed quasars and to evaluate the accuracy that can be realistically achieved on the value of H_0. Methods: We consider 14 lensed quasars...
Gillon, M., Pont, F., Moutou, C., Bouchy, F., Courbin, F., Sohy, S., ...
A high accuracy photometry algorithm is needed to take full advantage of the potential of the transit method for the characterization of exoplanets, especially in deep crowded fields. It has to...
Gillon, M., Pont, F., Moutou, C., Bouchy, F., Courbin, F., Sohy, S., ...
A high accuracy photometry algorithm is needed to take full advantage of the potential of the transit method for the characterization of exoplanets, especially in deep crowded fields. It has to...
VLT on-axis spectroscopy of quasar host galaxies (2006)
Letawe, G., Magain, P., Courbin, F., Jablonka, P., Meylan, G., Jahnke, K., ...
We present the full analysis of our sample of 20 bright low redshift quasars (MB < -23 and z < 0.35), observed spectroscopically with the VLT FORS1, with objectives of characterizing the hosts and...
Eigenbrod, A., Courbin, F., Meylan, G., Vuissoz, C., Magain, P.
Aims: We measure the redshift of the lensing galaxy in eight gravitationally lensed quasars in view of determining the Hubble parameter H_0 from the time delay method. Methods: Deep VLT/FORS1 spectra...
Eigenbrod, A., Courbin, F., Dye, S., Meylan, G., Sluse, D., Saha, P., ...
(Abridged) We present our VLT/FORS1 deep spectroscopic observations of the gravitationally lensed quasar SDSS J0924+0219, as well as archival HST/NICMOS and ACS images of the same object. The...
A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars (2005)
Faure, C., Alloin, D., Courbin, F.
In this paper we present new ESO/VLT FORS1 and ISAAC images of the fields around eight gravitationally lensed quasars: CTQ414, HE0230-2130, LBQS1009-0252, B1030+074, HE1104-1805, B1359+154, H1413+117...
LBQS 1429-0053: a binary quasar rather than a lensed quasar (2005)
Faure, C., Alloin, D., Gras, S., Courbin, F., Hudelot, P.
Very deep ESO/VLT FORS1 and ISAAC images, as well as HST NICMOS2 data are used to infer the nature of the quasar pair LBQS 1429-0053 A and B, either a binary quasar or a doubly-imaged lensed quasar....
The lensing system towards the doubly imaged quasar SBS 1520+530 (2005)
Faure, C., Courbin, F., Alloin, D., Bolzonella, M., Burud, I.
The gravitational potential responsible for the lensing effect in SBS 1520+530 is studied over length scales from a few arc-seconds to a few arc-minutes. For this purpose, we use sharply deconvolved...
Courbin, F., Letawe, G., Magain, P., Wisotzki, L., Jablonka, P., Jahnke, K., ...
We present the first result of a comprehensive spectroscopic study of quasar host galaxies. On-axis, spatially resolved spectra of low redshift quasars have been obtained with FORS1, mounted on the...
ZEN and the search for high-redshift galaxies (2005)
Willis, J. P., Courbin, F., Kneib, J-P., Minniti, D.
We present the ZEN (z equals nine) survey: a deep, narrow J-band search for proto-galactic Lya emission at redshifts z=9. In the first phase of the survey, dubbed ZEN1, we combine an exceptionally...
On the potential of extrasolar planet transit surveys (2005)
Gillon, M., Courbin, F., Magain, P., Borguet, B.
We analyse the respective benefits and drawbacks of ground-based and space-based transit surveys for extrasolar planets. Based on simple but realistic assumptions about the fraction of lower main...
Nakos, Th., Courbin, F., Poels, J., Libbrecht, C., Magain, P., Surdej, J., ...
We present the results of two-band CCD photometric monitoring of the gravitationally lensed quasar Q 0142-100 (UM 673).The data, obtained at ESO-La Silla with the 1.54 m Danish telescope in the Gunn...
Meylan, G., Courbin, F., Lidman, C., Tacconi-Garman, L. E.
We report on new high-resolution near-infrared images of the gravitationally lensed radio source PKS1830-211, a quasar at z=2.507. These adaptive optics observations, taken with the Very Large...
Eigenbrod, A., Courbin, F., Vuissoz, C., Meylan, G., Saha, P., Dye, S.
We use numerical simulations to test a broad range of plausible observational strategies designed to measure the time delay between the images of gravitationally lensed quasars. Artificial quasar...
ZEN and the search for high-redshift galaxies (2005)
Willis, J. P., Courbin, F., Kneib, J-P., Minniti, D.
We present the ZEN (z equals nine) survey: a deep, narrow J-band search for proto-galactic Lya emission at redshifts z=9. In the first phase of the survey, dubbed ZEN1, we combine an exceptionally...
ZEN and the search for high-redshift galaxies (2005)
Willis, J. P., Courbin, F., Kneib, J-P., Minniti, D.
We present the ZEN (z equals nine) survey: a deep, narrow J-band search for proto-galactic Lya emission at redshifts z=9. In the first phase of the survey, dubbed ZEN1, we combine an exceptionally...
Nakos, T., Courbin, F., Poels, J., Libbrecht, C., Magain, P., Surdej, J., ...
We present the results of two-band CCD photometric monitoring of the gravitationally lensed quasar Q 0142-100 (UM 673). The data, obtained at ESO-La Silla with the 1.54 m Danish telescope in the Gunn...
An optical time delay for the double gravitational lens system FBQ 0951+2635. (2005)
Jakobsson, P., Hjorth, J., Burud, I., Letawe, G., Lidman, C., Courbin, F.
Nakos, T., Courbin, F., Poels, J., Libbrecht, C., Magain, P., Surdej, J., ...
We present the results of two-band CCD photometric monitoring of the gravitationally lensed quasar Q 0142-100 (UM 673). The data, obtained at ESO-La Silla with the 1.54 m Danish telescope in the Gunn...
Nakos, T., Courbin, F., Poels, J., Libbrecht, C., Magain, P., Surdej, J., ...
We present the results of two-band CCD photometric monitoring of the gravitationally lensed quasar Q 0142-100 (UM 673). The data, obtained at ESO-La Silla with the 1.54 m Danish telescope in the Gunn...
Nakos, T., Courbin, F., Poels, J., Libbrecht, C., Magain, P., Surdej, J., ...
We present the results of two-band CCD photometric monitoring of the gravitationally lensed quasar Q 0142-100 (UM 673). The data, obtained at ESO-La Silla with the 1.54 m Danish telescope in the Gunn...
A deep, narrow J-band search for proto-galactic Lyman Alpha emission at redshifts z~9 (2004)
We present a deep, narrow J-band search for proto--galactic Lyman Alpha emission at redshifts z~9. We combine an exceptionally deep image of the Hubble Deep Field South, obtained using a narrow band...
An optical time delay for the double gravitational lens system FBQ 0951+2635 (2004)
Jakobsson, P., Hjorth, J., Burud, I., Letawe, G., Lidman, C., Courbin, F.
We present optical R-band light curves of the double gravitationally lensed quasar FBQ 0951+2635 from observations obtained at the Nordic Optical Telescope between March 1999 and June 2001. A time...
A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars (2004)
Faure, C., Alloin, D., Courbin, F.
In this paper we present new ESO/VLT FORS1 and ISAAC images of the fields around eight gravitationally lensed quasars: CTQ414, HE0230-2130, LBQS1009-0252, B1030+074, HE1104-1805, B1359+154, H1413+117...
Letawe, G., Courbin, F., Magain, P., Hilker, M., Jablonka, P., Jahnke, K., ...
VLT on-axis optical spectroscopy of the z=0.144 radio-loud quasar HE 1434-1600 is presented. The spatially resolved spectra of the host galaxy are deconvolved and separated from those of the central...
A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars (2004)
Faure, C., Alloin, D., Courbin, F.
In this paper we present new ESO/VLT FORS1 and ISAAC images of the fields around eight gravitationally lensed quasars: CTQ414, HE0230-2130, LBQS1009-0252, B1030+074, HE1104-1805, B1359+154, H1413+117...
A search for clusters and groups of galaxies on the line of sight towards 8 lensed quasars (2004)
Faure, C., Alloin, D., Courbin, F.
In this paper we present new ESO/VLT FORS1 and ISAAC images of the fields around eight gravitationally lensed quasars: CTQ414, HE0230-2130, LBQS1009-0252, B1030+074, HE1104-1805, B1359+154, H1413+117...
A quadruply imaged quasar with an optical Einstein ring candidate: 1RXS J113155.4-123155 (2003)
Sluse, D., Surdej, J., Hutsemekers, D., Jean, C., Courbin, F., ...
We report the discovery of a new quadruply imaged quasar surrounded by an optical Einstein ring candidate. Spectra of the different components of 1RXS J113155.4-123155 reveal a source at z=0.658. Up...
Quasar Lensing: the Observer's Point of View (2003)
The determination of the Hubble parameter H_0 is probably one of the most important applications of quasar lensing. The method, based on the measurement of the so-called ``time-delay'' between the...
LBQS 1429-0053: a binary quasar rather than a lensed quasar (2003)
Faure, C., Alloin, D., Gras, S., Courbin, F., Hudelot, P.
Very deep ESO/VLT FORS1 and ISAAC images, as well as HST NICMOS2 data are used to infer the nature of the quasar pair LBQS 1429-0053 A and B, either a binary quasar or a doubly-imaged lensed quasar....
LBQS 1429-0053: a binary quasar rather than a lensed quasar (2003)
Faure, C., Alloin, D., Gras, S., Courbin, F., Hudelot, P.
Very deep ESO/VLT FORS1 and ISAAC images, as well as HST NICMOS2 data are used to infer the nature of the quasar pair LBQS 1429-0053 A and B, either a binary quasar or a doubly-imaged lensed quasar....
LBQS 1429-0053: a binary quasar rather than a lensed quasar (2003)
Faure, C., Alloin, D., Gras, S., Courbin, F., Hudelot, P.
Very deep ESO/VLT FORS1 and ISAAC images, as well as HST NICMOS2 data are used to infer the nature of the quasar pair LBQS 1429-0053 A and B, either a binary quasar or a doubly-imaged lensed quasar....
Courbin, F., Letawe, G., Magain, P., Wisotzki, L., Jablonka, P., Jahnke, K., ...
We present the first result of a comprehensive spectroscopic study of quasar host galaxies. On-axis, spatially resolved spectra of low redshift quasars have been obtained with FORS1, mounted on the...
Courbin, F., Saha, P., Schechter, P. L.
Massive structures, such as galaxies, act as strong gravitational lenses on background sources. When the background source is a quasar, several lensed images are seen, as magnified or de-magnified...
Time delay and lens redshift for the doubly imaged BAL quasar SBS1520+530 (2002)
Burud, I., Hjorth, J., Courbin, F., Cohen, J. G., Magain, P., Jaunsen, A. O., ...
We present optical R-band light curves of the gravitationally lensed quasar SBS1520+530 derived from data obtained at the Nordic Optical Telescope. A time delay of 130+/-3 days (1 sigma) is...
Cosmic alignment towards the radio Einstein ring PKS 1830-211 ? (2002)
Courbin, F., Meylan, G., Kneib, J. P., Lidman, C.
Optical and near-IR Hubble Space Telescope and Gemini-North adaptive optics images, further improved through deconvolution, are used to explore the gravitationally lensed radio source PKS 1830-211....
The lensing system towards the doubly imaged quasar SBS 1520+530 (2002)
Faure, C., Courbin, F., Kneib, J. P., Alloin, D., Bolzonella, M., Burud, I.
The gravitational potential responsible for the lensing effect in SBS 1520+530 is studied over length scales from a few arc-seconds to a few arc-minutes. For this purpose, we use sharply deconvolved...
The lensing system towards the doubly imaged quasar SBS 1520+530 (2002)
Faure, C., Courbin, F., Alloin, D., Bolzonella, M., Burud, I.
The gravitational potential responsible for the lensing effect in SBS 1520+530 is studied over length scales from a few arc-seconds to a few arc-minutes. For this purpose, we use sharply deconvolved...
Courbin, F., Letawe, G., Magain, P., Wisotzki, L., Jablonka, P., Jahnke, K., ...
We present the first result of a comprehensive spectroscopic study of quasar host galaxies. On-axis, spatially resolved spectra of low redshift quasars have been obtained with FORS1, mounted on the...
The lensing system towards the doubly imaged quasar SBS 1520+530 (2002)
Faure, C., Courbin, F., Alloin, D., Bolzonella, M., Burud, I.
The gravitational potential responsible for the lensing effect in SBS 1520+530 is studied over length scales from a few arc-seconds to a few arc-minutes. For this purpose, we use sharply deconvolved...
Courbin, F., Letawe, G., Magain, P., Wisotzki, L., Jablonka, P., Jahnke, K., ...
We present the first result of a comprehensive spectroscopic study of quasar host galaxies. On-axis, spatially resolved spectra of low redshift quasars have been obtained with FORS1, mounted on the...
An Optical Time-Delay for the Lensed BAL Quasar HE2149-2745 (2001)
Burud, I., Courbin, F., Magain, P., Lidman, C., Hutsemekers, D., ...
We present optical V and i-band light curves of the gravitationally lensed BAL quasar HE2149-2745. The data, obtained with the 1.5m Danish Telescope (ESO-La Silla) between October 1998 and December...