2023/10/04 by Jordan C. J. D’Silva, Simon P. Driver, D'Silva, Jordan C. J. +9 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2310.03081
openalex publication_date 2023/10/04 · openalex created_date 2023/10/08 · openalex updated_date 2026/07/28
We consider the effect of including an active galactic nuclei (AGN) component when fitting spectral energy distributions of 109 spectroscopically confirmed z≈ 3.5-12.5 galaxies with JWST. Remarkably, we find that the resulting cosmic star formation history is ≈ 0.4 dex lower at z\gtrsim 9.5 when an AGN component is included in the fitting. This alleviates previously reported excess star formation at z\gtrsim 9.5 compared to models based on typical baryon conversion efficiencies inside dark matter halos. We find that the individual stellar masses and star formation rates can be as much as ≈ 4 dex lower when fitting with an AGN component. These results highlight the importance of considering both stellar mass assembly and supermassive black hole growth when interpreting the light distributions of among the first galaxies to ever exist.