Séminaire/Seminar Galaxies |
| « Investigating high-redshift AGN and 'Little Red Dots' with gravitational lensing » |
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Lukas Furtak |
| The advent of the JWST and its phenomenal near-infrared sensitivity and spatial resolution has enabled us over the last few years to uncover a new and rich population of extremely red active galactic nuclei (AGN) at high redshifts dubbed "Little Red Dots" (LRDs). Many properties of LRDs, to their very origin, remain mysterious and they remain one of the most prolific fields of JWST research into the early Universe. Ever since their first discovery, strong gravitational lensing (SL) has represented a sheer treasure trove of information for LRD science through the magnification, which enables us to probe fainter and smaller objects, and time-delays between multiple images, which allow us to measure long-term variability in humane time scales. While many LRDs are known in blank fields, the sample of multiply-imaged LRDs remains very limited. With the VENUS JWST cycle 4 program delivering new JWST imaging and spectroscopy of 60 SL fields, the time has come to expand this sample. In VENUS, we have thus-far detected a handful of new multiply-imaged LRDs at z~3-6, and more SL fields are being observed almost every week. In my talk, I will give an overview of what gravitational lensing can do for LRD and AGN studies, and present our ongoing efforts to build a statistical sample of lensed LRDs and other high-redshift AGN, as well as some preliminary results. With several magnified and multiply-imaged LRDs, we will be able to investigate in unprecedented detail where they fit into our picture of galaxy and AGN formation and the co-evolution of galaxies and black holes. |
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jeudi 5 février 2026 - 16:00 Amphithéâtre Henri Mineur Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |