Physical Characterization of Early Galaxies in the Webb's First Deep Field SMACS J0723.3-7323

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This paper highlights initial photometric analyses of JWST NIRCam imaging data in the sightline of SMACS0723, aiming to identify galaxies at redshift $z>7$.

• By applying a conservative Lyman-break selection followed by photometric redshift analysis and visual inspection, we identify four F090W-dropout and two F150W-dropout sources, three of which were recently confirmed in an independent spectroscopic analysis to $z=7.663$, 7.665, and 8.499.
• We then supplement our sample with a photometric-redshift selection, and identify five additional candidates at $7<z_{\rm phot}<13$.
• The NIRCam images clearly resolve all sources and reveal their sub-galactic components that were not resolved/detected in the previous imaging by Hubble Space Telescope.