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Concept

Courbe de lumière

Publications associées (30)

The Third Gravitational Lensing Accuracy Testing (Great3) Challenge Handbook

Frédéric Courbin, Marc Gentile

The GRavitational lEnsing Accuracy Testing 3 (GREAT3) challenge is the third in a series of image analysis challenges, with a goal of testing and facilitating the development of methods for analyzing astronomical images that will be used to measure weak gr ...

University of Chicago Press2014

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XIII. Time delays and 9-yr optical monitoring of the lensed quasar RX J1131-1231

Frédéric Courbin, Georges Meylan, Malte Tewes, Nicolas Jacques Joseph Marie Cantale

We present the results from nine years of optically monitoring the gravitationally lensed z(QSO) = 0.658 quasar RX J1131-1231. The R-band light curves of the four individual images of the quasar were obtained using deconvolution photometry for a total of 7 ...

Edp Sciences S A2013

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XI. Techniques for time delay measurement in presence of microlensing

Frédéric Courbin, Georges Meylan, Malte Tewes

Measuring time delays between the multiple images of gravitationally lensed quasars is now recognized as a competitive way to constrain the cosmological parameters, and it is complementary with other cosmological probes. This requires long and well sampled ...

Edp Sciences S A2013

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XIV. Time delay of the doubly lensed quasar SDSS J1001+5027

Frédéric Courbin, Georges Meylan, Malte Tewes

This paper presents optical R-band light curves and the time delay of the doubly imaged gravitationally lensed quasar SDSS J1001+5027 at a redshift of 1.838. We have observed this target for more than six years, between March 2005 and July 2011, using the ...

Edp Sciences S A2013

The ESPRI project: astrometric exoplanet search with PRIMA I. Instrument description and performance of first light observations

Ludger Weber

Context. The ESPRI project relies on the astrometric capabilities offered by the PRIMA facility of the Very Large Telescope Interferometer for discovering and studying planetary systems. Our survey consists of obtaining high-precision astrometry for a larg ...

Edp Sciences S A2013

Polar ring galaxies as tests of gravity

Olivier Pierre Marie Tiret

Polar ring galaxies are ideal objects with which to study the three-dimensional shapes of galactic gravitational potentials since two rotation curves can be measured in two perpendicular planes. Observational studies have uncovered systematically larger ro ...

Oxford Univ Press2013

The two-dimensional array of 2048 tilting micromirrors for astronomical spectroscopy

Nico de Rooij, Wilfried Noell, Michael David Canonica

In multi-object spectrometers, field selectors, which are located in the focal plane of the telescopes, are required for the selection of astronomical objects, such as stars or faint galaxies. We present a two-dimensional micromirror array as a field selec ...

Institute of Physics2013

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XII. Time delays of the doubly lensed quasars SDSS J1206+4332 and HS 2209+1914

Frédéric Courbin, Georges Meylan, Malte Tewes

Aims. Within the framework of the COSMOGRAIL collaboration we present 7- and 8.5-year-long light curves and time-delay estimates for two gravitationally lensed quasars: SDSS J1206+4332 and HS 2209+1914. Methods. We monitored these doubly lensed quasars in ...

Edp Sciences S A2013

La détection de périodicités cachées

Jean-Marc Nicoletti

This thesis is a small part of the preparation of the launch of the Gaia mission, a satellite of the European Space Agency (ESA). One of the goals of the mission is to perform a classification among variable stars considering different attributes. Periodic ...

EPFL2012

Simultaneous estimation of time delays and quasar structure

Frédéric Courbin, Georges Meylan, Christel Vuissoz

We expand our Bayesian Monte Carlo method for analyzing the light curves of gravitationally lensed quasars to simultaneously estimate time delays and the sizes of quasar continuum emission regions including their mutual uncertainties. We apply the method t ...

2008