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Arxiv: EPOCHS I. The Discovery and Star Forming Properties of Galaxies in the Epoch of Reionization at 6.5 < z < 18 with PEARLS and Public JWST data Published: 7/20/2024 11:18:59 PM Updated: 7/20/2024 11:18:59 PM

Paper abstract: We present in this paper the discovery, properties, and a catalog of 1165high redshift 6.5 < z < 18 galaxies found in deep JWST NIRCam imaging fromthe GTO PEARLS survey combined with data from JWST public fields. We describeour bespoke homogeneous reduction process and our analysis of these areasincluding the NEP, CEERS, GLASS, NGDEEP, JADES, and ERO SMACS-0723 fields withover 214 arcmin^{2} imaged to depths of ~ 30 mag. We describe ourrigorous methods for identifying these galaxies, involving the use ofLyman-break strength, detection significance criteria, visual inspection, andintegrated photometric redshifts probability distributions predominately athigh redshift. Our sample is a robust and highly pure collection of distantgalaxies from which we also remove brown dwarf stars, and calculatecompleteness and contamination from simulations. We include a summary of thebasic properties of these z > 6.5 galaxies, including their redshiftdistributions, UV absolute magnitudes, and star formation rates. Our study ofthese young galaxies reveals a wide range of stellar population properties asseen in their colors and SED fits which we compare to stellar populationmodels, indicating a range of star formation histories, dust, AGN and/ornebular emission. We find a strong trend exists between stellar mass and(U-V) color, as well as the existence of the `main-sequence' of starformation for galaxies as early as z ~ 12. This indicates that stellarmass, or an underlying variable correlating with stellar mass, is drivinggalaxy formation, in agreement with simulation predictions. We also discoverultra-high redshift candidates at z > 12 in our sample and describe theirproperties. Finally, we note a significant observed excess of galaxies comparedto models at z > 12, revealing a tension between predictions and ourobservations.