James Webb Space Telescope Feed Post

Arxiv: Photometric detection at 7.7\ μ\mathrm{m} of a galaxy beyond redshift 14 with JWST/MIRI Published: 5/28/2024 9:00:00 PM Updated: 1/16/2025 11:29:19 PM

Paper abstract: The James Webb Space Telescope (JWST) has spectroscopically confirmednumerous galaxies at z > 10. While weak rest-ultraviolet emission lines haveonly been seen in a handful of sources, the stronger rest-optical emissionlines are highly diagnostic and accessible at mid-infrared wavelengths with theMid-Infrared Instrument (MIRI) of JWST. We report the photometric detection ofthe distant spectroscopically confirmed galaxy JADES-GS-z14-0 at z =14.32^{+0.08}_{-0.20} with MIRI at 7.7\ \mu\mathrm{m}. The most plausiblesolution for the stellar population properties is that this galaxy containshalf a billion solar masses in stars with a strong burst of star formation inthe most recent few million years. For this model, at least one-third of theflux at 7.7\ \mu\mathrm{m} comes from the rest-optical emission lines\mathrm{H}\beta and/or \mathrm{[OIII]}\lambda\lambda4959,5007. The inferredproperties of JADES-GS-z14-0 suggest rapid mass assembly and metal enrichmentduring the earliest phases of galaxy formation. This work demonstrates theunique power of mid-infrared observations in understanding galaxies at theredshift frontier.