70 AIM, UMR 7158, CEA/DRF, CNRS, Université Paris Diderot, Irfu/Service d'Astrophysique,
Centre de Saclay, FR-91191 Gif-sur-Yvette, France

Intermediate-mass black holes (IMBHs), with masses in the range 1 0 0–1 0 6 M⊙, are the
link between stellar-mass BHs and supermassive BHs (SMBHs). They are thought to be the …

We present a new catalogue of∼ 2400 optically selected quasars with spectroscopic
redshifts and X-ray observations from either Chandra or XMM–Newton. The sample can be …

How quasars powered by supermassive black holes formed less than a billion years after
the Big Bang is still one of the outstanding problems in astrophysics, 20 years after their …

Understanding the formation and growth of supermassive black holes (SMBHs) at high
redshift represents a major challenge for theoretical models. In this work, we investigate the …

In recent years, the discovery of massive quasars at has provided a striking challenge to our
understanding of the origin and growth of supermassive black holes in the early Universe …

We study star cluster formation in a low-metallicity environment using three-dimensional
hydrodynamic simulations. Starting from a turbulent cloud core, we follow the formation and …

In this paper, we provide predictions for the black hole (BH) population that would be
observable with planned JWST surveys at 5≤ z≤ 15. We base our study on the recently …

The next generation of ground-based gravitational-wave detectors will observe
coalescences of black holes and neutron stars throughout the cosmos, thousands of them …

Recent discoveries of massive black holes (MBHs) in dwarf galaxies suggest that they may
have a more common presence than once thought. Systematic searches are revealing more …