  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. Our
spectral energy distribution analysis reveals that the selected galaxies are
characterized by young stellar populations (median age of $\sim50$ Myr) of
sub-solar metallicity ($\sim0.2\,Z_\odot$) and little dust attenuation
($A_{V}\sim0.5$). In several cases, we observe extreme Hb+[OIII] lines being
captured in the F444W band and seen as color excess, which is consistent with
their observed high star formation rate surface density. Eight of the 11
sources identified in this study appear in at least one of the recent studies
of the same fields (Adams et al., Atek et al., Donnan et al., Harikane et al.,
Yan et al.), implying the high fidelity of our selection. We cross-match all
high-$z$ galaxy candidates presented in the five studies with our catalog and
discuss the possible causes of discrepancy in the final lists.
