Speaker
Description
Studies of massive black holes (MBHs) have been extended to higher redshifts through recent discoveries enabled by the James Webb Space Telescope, providing key constraints on the processes governing MBH formation, commonly referred to as MBH seeding. However, the origin of the first MBHs remains uncertain, with several competing hypotheses under investigation. One leading scenario involves the formation of light MBH seeds (~100 M$_\odot$), thought to be remnants of Population III stars. Alternative scenarios propose the formation of intermediate-mass or heavy seeds at z > 7, either through runaway stellar collisions in dense star clusters or via the direct collapse of gas clouds under conditions that suppress cooling and fragmentation. Observations of high-redshift quasars further complicate this picture, as such rapid growth would require sustained Eddington-limited accretion over much of the age of the Universe, despite the expected effects of radiative feedback.
In this work, we analyze a unique system to explore potential solutions to these discrepancies. We present new JWST/NIRSpec IFU observations of a low-metallicity galaxy with a stellar mass of ~10$^9$ M$_\odot$ at z = 7.2, harboring a black hole located ~2.7 kpc off-center. The black hole, with a mass of ~10$^8$ M$_\odot$, is accreting close to the Eddington limit and significantly impacts the host galaxy, driving variations in the ionization parameter and producing clear spatial gradients from its position. With these results we provide new constraints on black hole growth and feedback in the early Universe.
| Collaborators (if any) | Stefano Carniani, Giacomo Venturi, Francesco Ziparo, Eleonora Parlanti |
|---|