Abstract
The James Webb Space Telescope opens a new window to directly probe luminous quasars powered by billion solar mass black holes in the Epoch of Reionization and their coevolution with massive galaxies with unprecedented details. In this paper, we report the first results from a deep NIRSpec integral field unit spectroscopic study of a quasar at z = 7.5. We obtain a bolometric luminosity of similar to 1.8 x 1047 erg s-1 and a black hole mass of similar to 0.7-2.5 x 109 M circle dot based on the H beta emission line in the quasar spectrum. We discover similar to 2 kpc scale, highly blueshifted (similar to-870 km s-1) and broad (similar to 1400 km s-1) [O iii] line emission after the quasar point-spread function has been subtracted. Such line emission most likely originates from a fast, quasar-driven outflow, the earliest one at galactic scales known so far. The dynamical properties of this outflow fall within the typical ranges of quasar-driven outflows at lower redshift, and the outflow may be fast enough to reach the circumgalactic medium. Combining both the extended and nuclear outflow together, the mass outflow rate, similar to 300 M circle dot yr-1, is similar to 60%-380% of the star formation rate of the quasar host galaxy, suggesting that the outflow may expel a significant amount of gas from the inner region of the galaxy. The kinetic energy outflow rate, similar to 3.6 x 1044 erg s-1, is similar to 0.2% of the quasar bolometric luminosity, which is comparable to the minimum value required for negative feedback based on simulation predictions. The dynamical timescale of the extended outflow is similar to 1.7 Myr, consistent with the typical quasar lifetime in this era.