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Adding Value to JWST Spectra and Photometry: Stellar Population and Star Formation Properties of Spectroscopically Confirmed JADES and CEERS Galaxies at z > 7 Published: 9/26/2023 5:29:02 PM Updated: 9/26/2023 5:29:02 PM

Paper abstract: In this paper, we discuss measurements of the stellar population and starforming properties for 43 spectroscopically confirmed publicly availablehigh-redshift z > 7 JWST galaxies in the JADES and CEERS observationalprograms. We carry out a thorough study investigating the relationship betweenspectroscopic features and photometrically derived ones, including fromspectral energy distribution (SED) fitting of models, as well as morphologicaland structural properties. We find that the star formation rates (SFRs)measured from H\beta line emission are higher than those estimated fromBayesian SED fitting and UV luminosity, with ratios SFR_{H\beta}/ SFR_{UV}ranging from 2~13. This is a sign that the star formation history isconsistently rising given the timescales of H\beta vs UV star formationprobes. In addition, we investigate how well equivalent widths (EWs) ofH\beta \lambda4861, [O III] \lambda4959, and [O III] \lambda5007 can bemeasured from photometry, finding that on average the EW derived fromphotometric excesses in filters is 30% smaller than the direct spectroscopicmeasurement. We also discover that a stack of the line emitting galaxies showsa distinct morphology after subtracting imaging that contains only thecontinuum. This gives us a first view of the line or ionized gas emission fromz > 7 galaxies, demonstrating that this material has a similar distribution,statistically, as the continuum. We also compare the derived SFRs and stellarmasses for both parametric and non-parametric star formation histories, wherewe find that 35% of our sample formed at least 30% of their stellar mass inrecent (< 10 Myr) starburst events.