Séminaire/Seminar Galaxies |
| « The Halo Effect: unraveling galaxy evolution in overdense regions at the Cosmic Noon » |
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Sofia Gallego |
| Galaxies are embedded within a network of interconnected filaments, essential for their formation and growth. Simultaneously, they emit radiation and enriched matter back into their environment, influencing the evolution of cosmic gas. Recent advancements in wide-field spectrographs offer a unique perspective, allowing us to probe the spatial distribution and properties of the circumgalactic medium at high redshift, particularly the Lyman-alpha line emitted by cold hydrogen gas. These insights are especially valuable in overdense regions, like protoclusters and groups, where we can explore most of the physical mechanisms at play. In this context, I will present a multi-wavelength analysis of protoclusters at the cosmic noon, revealing a unique opportunity to investigate the evolution of galaxies at an epoch of enhanced star formation, where environmental effects are most significant. Leveraging extensive data across the near-infrared to ultraviolet, we uncover a group of extended halos with complex morphological and kinematical features in Lyman-alpha, CIV, and HeII, connected to interacting galaxies, mergers, and a remarkably high local density of AGN activity. Our findings suggest ongoing feedback processes between AGNs and the surrounding gas, and highlight the influence of active galactic nuclei on protocluster environments at z = 2.8. We also provide evidence of the role of quasar properties in shaping gas dynamics, linking them with feedback mechanisms affecting both the circumgalactic and intergalactic media. These observations underscore the need for theoretical interpretations of galaxy-gas interactions on intergalactic scales, as well as serving as a precursor to future large surveys that will enhance our understanding of galaxy evolution within the cosmic web. |
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Thursday 24 October 2024 - 11:30 Salle Entresol Daniel Chalonge Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |