Measuring neutrino masses with joint JWST and DESI DR2 data

Early James Webb Space Telescope (JWST) observations reveal an unexpectedly abundant population of high-redshift candidate massive galaxies at $z\ensuremath{\gtrsim}7$, and recent Dark Energy Spectroscopic Instrument (DESI) measurements show a preference for dynamical dark energy, which together present a significant challenge to the standard $\mathrm{\ensuremath{\Lambda}}$ cold dark matter ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) cosmology. In this work, we jointly analyze high-redshift galaxy data from JWST, baryon acoustic oscillations data from DESI Data Release 2 (DR2), and cosmic microwave background (CMB) data from Planck and Atacama Cosmology Telescope (ACT), measuring the total neutrino mass $\ensuremath{\sum}{m}_{\ensuremath{\nu}}$. We consider three dark energy models ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$, $w\mathrm{CDM}$, and ${w}_{0}{w}_{a}\mathrm{CDM}$) and three mass hierarchies. Our results indicate that in the ${w}_{0}{w}_{a}\mathrm{CDM}$ model, adding JWST data to $\mathrm{CMB}+\mathrm{DESI}$ tightens the upper limit of $\ensuremath{\sum}{m}_{\ensuremath{\nu}}$ by about 5.8%--10.2%, and we obtain $\ensuremath{\sum}{m}_{\ensuremath{\nu}}<0.167\text{ }\text{ }\mathrm{eV}$ ($2\ensuremath{\sigma}$) in the normal hierarchy (NH) case. Furthermore, JWST also offers indicative lower limits on star formation efficiency parameter of ${f}_{*,10}\ensuremath{\gtrsim}0.146--0.161$. Bayesian evidence weakly favors the ${w}_{0}{w}_{a}\mathrm{CDM}+\ensuremath{\sum}{m}_{\ensuremath{\nu}}(\mathrm{NH})$ model relative to the $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}+\ensuremath{\sum}{m}_{\ensuremath{\nu}}(\mathrm{NH})$ model using $\mathrm{CMB}+\mathrm{DESI}+\mathrm{JWST}$ data. These results suggest that the joint analysis of high-redshift JWST data and low-redshift DESI data provides useful constraints on neutrino mass and merits further investigation.