New galaxy UV luminosity constraints on warm dark matter from JWST

TL;DR

This paper uses recent JWST galaxy UV luminosity data at high redshifts to set new constraints on warm dark matter particle mass, improving previous limits and highlighting the potential of JWST for dark matter research.

Contribution

It introduces a novel analysis combining JWST and HST data to tighten constraints on warm dark matter particle mass, surpassing previous bounds.

Findings

New lower limit of 3.2 keV on WDM particle mass at 95% confidence.

Demonstrates JWST's potential to improve dark matter constraints with future observations.

Integrates galaxy luminosity functions with astrophysical and dark matter parameters.

Abstract

We exploit the recent {\it James Webb Space Telescope} (JWST) determination of galaxy UV luminosity functions over the redshift range $z=9-14.5$ to derive constraints on warm dark matter (WDM) models. The delayed structure formation in WDM universes make high-redshift observations a powerful probe to set limits on the particle mass $m_\mathrm{x}$ of WDM candidates. By integrating these observations with blank-field surveys conducted by the {\it Hubble Space Telescope} (HST) at redshifts $z=4-8$, we impose constraints on both astrophysical parameters ($\beta$, $\gamma$, $\epsilon_{\mathrm N}$, $M_c$ for a double-power law star formation efficiency, and $\sigma_{M_{\mathrm{UV}}}$ for a Gaussian magnitude-halo mass relation) and the WDM parameter (dark matter particle mass $m_\mathrm{x}$) simultaneously. We find a new limit of $m_\mathrm{x} \geq 3.2$ keV for the mass of thermal relic WDM particles at $95\%$ confidence level. This bound is tighter than the most stringent result derived using HST data before. Future JWST observations could further reduce the observation uncertainties and improve this constraint.