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arXiv · 2210.07249

A Search for Lensed Lyman-Alpha Emitters within the Early HETDEX Data Set

Isaac H. Laseter·Steven L. Finkelstein·Micaela J. Bagley·Dustin M. Davis·Karl Gebhardt·Caryl Gronwall·Robin Ciardullo·Gregory R. Zeimann·Erin Mentuch Cooper·Daniel Farrow
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Abstract

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) is a large-volume spectroscopic survey without pre-selection of sources, searching ~ 540 deg^2 for Lyman-alpha emitting galaxies (LAEs) at 1.9 < z < 3.5. Taking advantage of such a wide-volume survey, we perform a pilot study using early HETDEX data to search for lensed Lyman-alpha emitters. After performing a proof-of-concept using a previously known lensed LAE covered by HETDEX, we perform a search for previously unknown lensed LAEs in the HETDEX spectroscopic sample. We present a catalog of 26 potential LAEs lensed by foreground, red, non-star-forming galaxies at z ~ 0.4 - 0.7. We estimate the magnification for each candidate system, finding 12 candidates to be within the strong lensing regime (magnification $\mu$ > 2). Follow-up observations of these potential lensed LAEs have the potential to confirm their lensed nature and explore these distant galaxies in more detail.

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Isaac H. Laseter, Steven L. Finkelstein, Micaela J. Bagley, Dustin M. Davis, Karl Gebhardt, Caryl Gronwall, Robin Ciardullo, Gregory R. Zeimann, Erin Mentuch Cooper, Daniel Farrow. 2022-10-13. A Search for Lensed Lyman-Alpha Emitters within the Early HETDEX Data Set. https://doi.org/10.3847/1538-4357/ac9186

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