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We report the identification of 15 galaxy candidates at $z\ge9$ using theinitial COSMOS-Web JWST observations over 77 arcmin$^2$ through four NIRCamfilters (F115W, F150W, F277W, F444W) with an overlap with MIRI (F770W) of 8.7arcmin$^2$. We fit the sample using several publicly-available SED fitting andphotometric redshift codes and determine their redshifts between $z=9.3$ and$z=10.9$ ($\langle z\rangle=10.0$), UV-magnitudes between M$_{\rm UV}$ =$-$21.2 and $-$19.5 (with $\langle $M$_{\rm UV}\rangle=-20.2$) and rest-frameUV slopes ($\langle \beta\rangle=-2.4$). These galaxies are, on average, moreluminous than most $z\ge9$ candidates discovered by JWST so far in theliterature, while exhibiting similar blue colors in their rest-frame UV. Therest-frame UV slopes derived from SED-fitting are blue ($\beta\sim$[$-$2.0,$-$2.7]) without reaching extremely blue values as reported in other recentstudies at these redshifts. The blue color is consistent with models thatsuggest the underlying stellar population is not yet fully enriched in metalslike similarly luminous galaxies in the lower redshift Universe. The derivedstellar masses with $\langle \log_{\rm 10}($M$_\star/$M$_\odot)\rangle\approx8-9$ are not in tension with the standard$\Lambda$CDM model and our measurement of the volume density of such UVluminous galaxies aligns well with previously measured values presented in theliterature at $z\sim9-10$. Our sample of galaxies, although compact, aresignificantly resolved.

Unveiling the distant Universe: Characterizing $z\ge9$ Galaxies in the first epoch of COSMOS-Web