The coverage of the key surveys within PRIMER-COSMOS (left panel) and PRIMER-UDS (right panel). The background grayscale image presents the 3σ limiting depth (in 0﹩\mathop{.}\limits^{^{\prime\prime} }﹩2 diameter apertures) for point sources of the stacked JWST/NIRCam image, which is used for source detection. The blue, orange, and red lines show the coverage of the HST data from the CANDELS survey (A. Galametz et al. 2013; H. Nayyeri et al. 2017), the Magellan/Fourstar medium-band data from the ZFOURGE survey (C. M. S. Straatman et al. 2016), and the JWST/MIRI data taken with the PRIMER survey. The boundary of our mosaics in PRIMER-COSMOS is determined by the coverage of the JWST/MIRI data from PRIMER (J. S. Dunlop et al. 2021) and the deep SCUBA-2 data from STUDIES (W.-H. Wang et al. 2017; Z.-K. Gao et al. 2024).