GA-NIFS and EIGER: A merging quasar host at z=7 with an overmassive black hole

Understand

The James Webb Space Telescope is revolutionising our ability to understand the host galaxies and local environments of high-z quasars.

• Here we obtain a comprehensive understanding of the host galaxy of the z=7.08 quasar J1120+0641 by combining NIRSpec integral field spectroscopy with NIRCam photometry of the host continuum emission.
• Our emission-line maps reveal that this quasar host is undergoing a merger with a bright companion galaxy.
• The quasar host and the companion have similar dynamical masses of $\sim10^{10}M_\odot$, suggesting that this is a major galaxy interaction.