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arXiv · 2610.03572

Searching for Green Pea Galaxies in the SFACT Survey

Kristin N. Baker·John J. Salzer·Brooke Kimsey-Miller·Samantha W. Brunker·David J. Carr·Jennifer Sieben·Steven Janowiecki·Samir Salim
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Abstract

Green Pea galaxies (GPs) are a class of rare, extreme star-forming galaxies whose physical properties closely resemble high-redshift Ly-α emitting galaxies. Their high equivalent width [O III] emission lines make them readily identifiable in surveys of emission-line galaxies like the on-going deep, narrowband Star Formation Across Cosmic Times (SFACT) survey. In this study, we use broadband gri colors and [O III] equivalent widths derived from narrowband images to select a new sample of ~120 GP candidates from a catalog of [O III]-detected galaxies identified in the SFACT survey. All SFACT GP candidates have spectroscopically confirmed redshift in the range z = 0.31-0.51. The median apparent magnitude of our sample is g = 22.9. We compare the properties of our GP candidate sample to other samples of known GPs. We find that the excellent depth of SFACT allows us to detect GP candidates to lower luminosities than these comparison samples. This is the first catalog of SFACT GP candidates; additional candidates will be added as the spectroscopic follow-up of the SFACT survey is completed.

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Kristin N. Baker, John J. Salzer, Brooke Kimsey-Miller, Samantha W. Brunker, David J. Carr, Jennifer Sieben, Steven Janowiecki, Samir Salim. 2026-10-02. Searching for Green Pea Galaxies in the SFACT Survey. https://arxiv.org/abs/2610.03572

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