Matthias Bartelmann
Institut für Theoretische Astrophysik, Ruprecht-Karls-Universität Heidelberg (Heidelberg, Allemagne)
Salle des séminaires Évry Schatzman, Institut d'Astrophysique de Paris
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| « From shape measurement to cluster reconstruction: Some new methods in gravitational lensing » |
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Matthias Bartelmann |
| Gravitational lensing provides perhaps the most promising methods to detect and quantify dark matter distributions in the Universe. In detail, however, enormous problems have to be overcome. Weak gravitational lensing requires precise measurements of distortions of numerous faint and small background-galaxy images that provide information with relatively coarse angular resolution, while strong gravitational lensing is confined to tiny solid angles on the sky. I shall present and discuss a selection of new methods for gravitational lensing which (1) identify and reduce biases, (2) improve the deconvolution of point-spread functions, (3) clarify the measurement of higher-order lensing effects, (4) provide accurate reconstructions of mass distributions in galaxy clusters and (5) increase the efficiency of peak detections in the dark-matter distribution and clarify their interpretation. |
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vendredi 25 mars 2011 - 11:00 Salle des séminaires Évry Schatzman, Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |