AI Insight
This study proposes using the SHARP instrument on the Extremely Large Telescope to observe eleven obscured active galactic nuclei (AGN) at redshifts 1.5-2.5 that host both vigorous star formation and radio jets. The observations aim to map how AGN feedback—through both relativistic jets and radiation—affects the surrounding interstellar medium during a brief evolutionary phase lasting less than 100,000 years. By comparing spatial distributions of stellar populations, gas properties, and kinematics with radio jet structures, researchers will quantify how AGN feedback suppresses star formation in galaxies during the cosmic noon epoch when this process was most influential.
Why it matters
Understanding AGN feedback is crucial for explaining why massive galaxies stop forming stars and how supermassive black holes co-evolve with their host galaxies. This research targets a critical but poorly understood transitional phase that may determine the final properties of present-day massive galaxies.
Understand the Science
arXiv:2606.31673v1 Announce Type: new
Abstract: A highly star-forming galaxy at z ~ 2 hosting an obscured, luminous active galactic nucleus (AGN) and a relativistic radio jet sets the stage for a cosmic crime scene. The victim is star formation, the suspect is AGN feedback. These systems offer a rare opportunity to catch this process in the act. We propose SHARP@ELT integral-field spectroscopic observations of heavily obscured, luminous AGN with resolved radio emission to witness the onset of feedback and its impact on the host interstellar medium (ISM). Such objects trace a short-lived (< 10^5 yr) evolutionary phase in which a recent starburst, newly triggered radio jets, and a deeply embedded AGN coexist. In this phase, feedback is expected to suppress star formation while clearing the dusty nuclear regions. Using SHARP/VESPER, we will derive spatially resolved maps of stellar ages, star formation rate density, gas density, and ionization state, alongside the kinematics of stars and ionized gas. By directly comparing these properties with the radio structures, we will quantify the effects of both jet-driven and radiative feedback on the ISM. Our sample consists of eleven luminous, obscured AGN at 1.5 < z < 2.5 with resolved radio emission on scales of ~1-15 kpc. Exploiting the VESPER multi-Integral Field Selector capability, we will obtain resolved continuum and emission-line maps for at least 110 galaxies at cosmic noon, enabling a comprehensive characterization of their environment, multiphase ISM, and nuclear activity within 55 h of integration time. SHARP will thus reveal AGN feedback at the epoch when it is most effective, providing a decisive step toward understanding its role in galaxy evolution.