Misc,

Revealing Galaxy Candidates out to $z 16$ with JWST Observations of the Lensing Cluster SMACS0723

, , , , , , and .
(2022)cite arxiv:2207.12338Comment: 14 pages, 15 figures, 2 tables, submission to MNRAS.

Abstract

One of the main goals of the JWST is to study the first galaxies in the Universe. We present a systematic photometric analysis of very distant galaxies in the first JWST deep field towards the massive lensing cluster SMACS0723. As a result, we report the discovery of two galaxy candidates at $z\sim16$, only $250$ million years after the Big Bang. We also identify two candidates at $z12$ and 11 candidates at $z10-11$. Our search extended out to $złesssim21$ by combining color information across seven NIRCam and NIRISS filters. By modelling the Spectral Energy Distributions (SEDs) with EAZY and BEAGLE, we test the robustness of the photometric redshift estimates. While their intrinsic (un-lensed) luminosity is typical of the characteristic luminosity L$^*$ at $z>10$, our high-redshift galaxies typically show small sizes and their morphologies are consistent with disks in some cases. The highest-redshift candidates have extremely blue UV-continuum slopes $-3 < \beta <-2.5$, young ages $10-100$\,Myr, and stellar masses $łog(M_\star/M_ødot)=8.4-8.8$ inferred from their SED modeling which indicate a rapid build-up of their stellar mass. Our search clearly demonstrates the capabilities of JWST to uncover robust photometric candidates up to very high redshifts, and peer into the formation epoch of the first galaxies.

Tags

Users

  • @gpkulkarni

Comments and Reviews