Journal-club Postdoc |
| « AGN versus star formation: emission-line diagnostics at ultraviolet and optical wavelengths » |
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Anna Feltre |
| There is growing evidence for nuclear gravitational accretion onto supermassive black holes to coexist and coevolve with episodes of star formation. To disentangle the relative contributions of nuclear activity and star formation to the observed galaxy properties is particularly challenging. Over the past decades, spectroscopic studies have led to the identification of several diagnostic diagrams which successfully separate active galactic nuclei (AGN) from star-forming galaxies at optical and infrared wavelengths. We have recently developed new diagnostics of nebular emission from both active and inactive galaxies extending previous studies to the ultraviolet domain. In this talk, I will show how photo-ionisation models of nebular emission from star-forming galaxies and AGN can help us gain new insight into the physical properties of galaxies. I will then describe the way in which new ultraviolet and standard optical diagnostics can best help distinguish between nuclear and star formation activities in extragalactic sources. I will stress the importance of such results in the context of understanding the nature of the ionizing source within primeval galaxies. To conclude, I will highlight the relevance of such results for the interpretation of high-quality spectra from forthcoming facilities, such as JWST and extremely large ground based telescopes. |
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mardi 24 novembre 2015 - 11:00 Salle des séminaires Évry Schatzman, Institut d'Astrophysique |
| Page web du journal-club / Journal-club's webpage |