The Age of Discovery with the James Webb: Excavating the Spectral Signatures of the First Massive Black Holes

Understand

The James Webb Space Telescope (JWST) will open a new window of the most distant universe and unveil the early growth of supermassive black holes (BHs) in the first galaxies.

• In preparation for deep JWST imaging surveys, it is crucial to understand the color selection of high-redshift accreting seed BHs.
• We model the spectral energy distribution of super-Eddington accreting BHs with millions of solar masses in metal-poor galaxies at $z\gtrsim 8$, applying post-process line transfer calculations to radiation hydrodynamical simulation results.
• Ten kilosecond exposures with the NIRCam and MIRI broad-band filters are sufficient to detect the radiation flux from the seed BHs with bolometric luminosities of $L_{\rm bol}\simeq 10^{45}~{\rm erg~s}^{-1}$.