Using JADES NIRCam photometry to investigate the dependence of stellar mass inferences on the IMF in the early universe

Proc Natl Acad Sci U S A. 2024 Oct 15;121(42):e2317375121. doi: 10.1073/pnas.2317375121. Epub 2024 Oct 8.

Abstract

The detection of numerous and relatively bright galaxies at redshifts z > 9 has prompted new investigations into the star-forming properties of high-redshift galaxies. Using local forms of the initial mass function (IMF) to estimate stellar masses of these galaxies from their light output leads to galaxy masses that are at the limit allowed for the state of the Lambda Cold Dark Matter (ΛCDM) Universe at their redshift. We explore how varying the IMF assumed in studies of galaxies in the early universe changes the inferred values for the stellar masses of these galaxies. We infer galaxy properties with the spectral energy distribution (SED) fitting code Prospector using varying IMF parameterizations for a sample of 102 galaxies with photometry from the James Webb Space Telescope, JWST Advanced Deep Extragalactic Survey that are spectroscopically confirmed to be at [Formula: see text], with additional photometry from the JWST Extragalactic Medium Band Survey for twenty-one of the galaxies. We demonstrate that models with stellar masses reduced by a factor of three or more do not affect the modeled SED.

Keywords: James Webb Space Telescope; galaxy evolution; high-redshift galaxies; star formation.