The BoRG-JWST Survey: Program Overview and First Confirmations of Luminous Reionization-Era Galaxies from Pure-Parallel Observations

Guido Roberts-Borsani; Micaela Bagley; Sofía Rojas-Ruiz; Tommaso Treu; Takahiro Morishita; Steven L. Finkelstein; Michele Trenti; Pablo Arrabal Haro; Eduardo Bañados; Óscar A. Chávez Ortiz; Katherine Chworowsky; Taylor A. Hutchison; Rebecca L. Larson; Nicha Leethochawalit; Gene C. K. Leung; Charlotte Mason; Rachel S. Somerville; Massimo Stiavelli; L. Y. Aaron Yung; Susan A. Kassin; Christian Soto

arXiv · 2407.17551

The BoRG-JWST Survey: Program Overview and First Confirmations of Luminous Reionization-Era Galaxies from Pure-Parallel Observations

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Abstract

We present the BoRG-JWST survey, a combination of two JWST Cycle 1 programs aimed at obtaining NIRSpec spectroscopy of representative, UV-bright $7 5$, highlighting the large abundance of high-redshift galaxies even in individual WFC3 pointings. The primary sample span an absolute magnitude range $-20.4 7$ sources currently known and comparable to the brightest sources at $z>10$. Prominent [O III]+H$\beta$ lines are found across the full sample, while a stack of sources reveals a plethora of other rest-optical lines and additional rest-UV C III]1909 \r{A} emission. Despite their luminosities, none of the low-resolution spectra display evidence for Type 1 AGN activity based on a search for broad-line emission. Lastly, we present a spectroscopic data release of 188 confirmed $0.5\lesssim z\lesssim5.0$ sources from filler MSA observations, highlighting the legacy value of the survey and a representative benchmark for comparisons to deep field observations.

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Guido Roberts-Borsani, Micaela Bagley, Sofía Rojas-Ruiz, Tommaso Treu, Takahiro Morishita, Steven L. Finkelstein, Michele Trenti, Pablo Arrabal Haro, Eduardo Bañados, Óscar A. Chávez Ortiz, Katherine Chworowsky, Taylor A. Hutchison, Rebecca L. Larson, Nicha Leethochawalit, Gene C. K. Leung, Charlotte Mason, Rachel S. Somerville, Massimo Stiavelli, L. Y. Aaron Yung, Susan A. Kassin, Christian Soto. 2024-07-24. The BoRG-JWST Survey: Program Overview and First Confirmations of Luminous Reionization-Era Galaxies from Pure-Parallel Observations. https://arxiv.org/abs/2407.17551

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