Measuring neutrino masses with joint JWST and DESI DR2 data

Early JWST observations reveal an unexpectedly abundant population of high-redshift candidate massive galaxies at z 7, and recent DESI measurements show a preference for dynamical dark energy, which together present a significant challenge to the standard $Λ$CDM cosmology. In this work, we jointly analyze high-redshift galaxy data from JWST, baryon acoustic oscillations data from DESI DR2, and cosmic microwave background (CMB) data from Planck and ACT, measuring the total neutrino mass ∑ m_ν. We consider three dark energy models ($Λ$CDM, wCDM, and w₀wₐCDM) and three mass hierarchies. Our results indicate that in the w₀wₐCDM model, adding JWST data to CMB+DESI tightens the upper limit of ∑ m_ν by about $5.8%-10.2%$, and we obtain ∑ m_ν < 0.167~eV ($2σ$) in the normal hierarchy (NH) case. Furthermore, JWST also offers indicative lower limits on star formation efficiency parameter of f*,10 0.146-0.161. Bayesian evidence weakly favors the w₀wₐCDM+∑ m_ν(NH) model relative to the $Λ$CDM+∑ m_ν(NH) model using CMB+DESI+JWST data. These results suggest that the joint analysis of high-redshift JWST data and low-redshift DESI data provides compelling constraints on neutrino mass and merits further investigation.