{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/the-z-gtrsim-9-galaxy-uv-luminosity-function","title":"The $z \\gtrsim 9$ galaxy UV luminosity function from the JWST Advanced Deep Extragalactic Survey: insights into early galaxy evolution and reionization","arxiv_id":"2501.00984","date":"2025-01-02","proceeding":null,"authors":["Lily Whitler","Daniel P. Stark","Michael W. Topping","Brant Robertson","Marcia Rieke","Kevin N. Hainline","Ryan Endsley","Zuyi Chen","William M. Baker","Rachana Bhatawdekar","Andrew J. Bunker","Stefano Carniani","Stéphane Charlot","Jacopo Chevallard","Emma Curtis-Lake","Eiichi Egami","Daniel J. Eisenstein","Jakob M. Helton","Zhiyuan Ji","Benjamin D. Johnson","Pablo G. Pérez-González","Pierluigi Rinaldi","Sandro Tacchella","Christina C. Williams","Christopher N. A. Willmer","Chris Willott","Joris Witstok"],"abstract":"The high-redshift UV luminosity function provides important insights into the evolution of early galaxies. JWST has revealed an unexpectedly large population of bright ($M_\\mathrm{UV} \\lesssim -20$) galaxies at $z\\gtrsim10$, implying fundamental changes in the star forming properties of galaxies at increasingly early times. However, constraining the fainter population ($M_\\mathrm{UV} \\gtrsim -18$) has been more challenging. In this work, we present the $z\\gtrsim9$ UV luminosity function from the JWST Advanced Deep Extragalactic Survey. We calculate the UV luminosity function from several hundred $z\\gtrsim9$ galaxy candidates that reach UV luminosities of $M_\\mathrm{UV}\\sim-17$ in redshift bins of $z\\sim9-12$ (309 candidates) and $z\\sim12-16$ (63 candidates). We search for candidates at $z\\sim16-22.5$ and find none. We also estimate the $z\\sim14-16$ luminosity function from the $z\\geq14$ subset of the $z\\sim12-16$ sample. Consistent with other measurements, we find an excess of bright galaxies that is in tension with many theoretical models, especially at $z\\gtrsim12$. However, we also find high number densities at $-18\\lesssim M_\\mathrm{UV} \\lesssim-17$, suggesting that there is a larger population of faint galaxies than expected, as well as bright ones. From our parametric fits for the luminosity function, we find steep faint end slopes of $-2.5\\lesssim\\alpha\\lesssim-2.3$, suggesting a large population of faint ($M_\\mathrm{UV} \\gtrsim -17$) galaxies. Combined, the high normalization and steep faint end slope of the luminosity function could imply that the reionization process is appreciably underway as early as $z=10$.","url_abs":"https://arxiv.org/abs/2501.00984v1","url_pdf":"https://arxiv.org/pdf/2501.00984v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"the-z-gtrsim-9-galaxy-uv-luminosity-function","repo_url":"https://github.com/lwhitler/jades_highz_uvlf","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}