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Implications of the Stellar Mass Density of High-z Massive Galaxies from JWST on Warm Dark Matter Published: 6/9/2023 6:33:30 AM Updated: 6/9/2023 6:33:30 AM

Paper abstract: A significant excess of the stellar mass density at high redshift has beendiscovered from the early data release of James Webb Space Telescope(\it{JWST}), and it may require a high star formation efficiency. However,this will lead to large number density of ionizing photons in the epoch ofreionization (EoR), so that the reionization history will be changed, which canarise tension with the current EoR observations. Warm dark matter (WDM), viathe free streaming effect, can suppress the formation of small-scale structureas well as low-mass galaxies. This provides an effective way to decrease theionizing photons when considering a large star formation efficiency in high-zmassive galaxies without altering the cosmic reionization history. On the otherhand, the constraints on the properties of warm dark matter can be derived fromthe \it JWST observations. In this work, we study WDM as a possible solutionto reconcile the \it JWST stellar mass density of high-z massive galaxiesand reionization history. We find that the WDM particle mass withm_{\text{W}}~0.6 keV can match both the \it JWST high-z comovingcumulative stellar mass density and the reionization history, for a starformation efficiency parameter range f_{*}^{0} = 0.1 - 1.0.