The evolution of obscured AGN across cosmic time -- A large quasar survey for the 2040s

Tanya Urrutia; Darshan Kakkad; Paula Sánchez-Sáez; Mojtaba Raouf; Swayamtrupta Panda; Sarah E. I. Bosman; Francisco Pozo Nunez; Annagrazia Puglisi; Sophia Flury; Dragana Ilic; Andjelka B. Kovacevic; Mamta Pandey-Pommier; Giustina Vietri; Sarath Satheesh-Sheeba; Francesco Salvestrini; Susanna Bisogni; Eduardo Bañados; Ana Monreal Ibero; Sabine Thater; Pratika Dayal; Filippo D'Ammando; José Afonso; Paramita Barai; Valentin Ivanov

arXiv · 2512.18421

The evolution of obscured AGN across cosmic time -- A large quasar survey for the 2040s

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Abstract

We propose a large quasar demographic optical multi-object spectroscopic (MOS) survey targeting over 50 million AGN candidates up to the highest redshifts possible in the optical (z~6.5), with repeat visits, using a variety of selection criteria available by 2040. A large MOS survey combining all AGN selection methods is the only way to unify a diverse range of different obscured AGN populations within a single, variability- and spectroscopy-based framework, rather than as disjoint classes selected by different methods.

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Tanya Urrutia, Darshan Kakkad, Paula Sánchez-Sáez, Mojtaba Raouf, Swayamtrupta Panda, Sarah E. I. Bosman, Francisco Pozo Nunez, Annagrazia Puglisi, Sophia Flury, Dragana Ilic, Andjelka B. Kovacevic, Mamta Pandey-Pommier, Giustina Vietri, Sarath Satheesh-Sheeba, Francesco Salvestrini, Susanna Bisogni, Eduardo Bañados, Ana Monreal Ibero, Sabine Thater, Pratika Dayal, Filippo D'Ammando, José Afonso, Paramita Barai, Valentin Ivanov. 2025-12-20. The evolution of obscured AGN across cosmic time -- A large quasar survey for the 2040s. https://arxiv.org/abs/2512.18421

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