COOL-LAMPS. IV. A Sample of Bright Strongly Lensed Galaxies at 3 < z < 4

Abstract

We report the discovery of five bright, strong gravitationally lensed galaxies at 3 &lt; z &lt; 4: COOL J0101+2055 (z = 3.459), COOL J0104−0757 (z = 3.480), COOL J0145+1018 (z = 3.310), COOL J0516−2208 (z = 3.549), and COOL J1356+0339 (z = 3.753). These galaxies have magnitudes of r AB, z AB &lt; 21.81 mag and are lensed by galaxy clusters at 0.26 &lt; z &lt; 1. This sample nearly doubles the number of known bright lensed galaxies with extended arcs at 3 &lt; z &lt; 4. We characterize the lensed galaxies using ground-based grz/giy imaging and optical spectroscopy. We report model-based magnitudes and derive stellar masses, dust content, and star formation rates via stellar population synthesis modeling. Building lens models based on ground-based imaging, we estimate source magnifications ranging from ∼29 to ∼180. Combining these analyses, we derive demagnified stellar masses in the range log 10 ( M * / M ⊙ ) ∼ 9.69 − 10.75 and star formation rates in the youngest age bin in the range log 10 ( SFR / ( M ⊙ yr − 1 ) ) ∼ 0.39 − 1.46 , placing the sample galaxies on the massive end of the star-forming main sequence in this redshift interval. In addition, three of the five galaxies have strong Lyα emissions, offering unique opportunities to study Lyα emitters at high redshift in future work.

COOL-LAMPS. Discovery of COOL J0335−1927, a Gravitationally Lensed Quasar at z = 3.27 with an Image Separation of 23.″3

“…COOL J0335−1927 was discovered serendipitously by the COOL-LAMPS collaboration, as part of a systematic visual search for strong lenses (e.g., Khullar et al 2021;Sukay et al 2022;Zhang et al 2023) in public imaging data from the Dark Energy Camera Legacy Survey (DECaLS; Dey et al 2019). It was not flagged as a candidate WSLQ by the process described in Martinez et al (2023) because two of the three lensed quasar images (images B and C) in COOL J0335−1927 are classified in the DECaLS Data Release 9 catalog as extended sources (Sérsic profiles).…”