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Title: PEARLS: Near-infrared Photometry in the JWST North Ecliptic Pole Time Domain Field*

We present near-infrared (NIR) ground-basedY,J,H, andKimaging obtained in the James Webb Space Telescope (JWST) North Ecliptic Pole Time Domain Field (NEP TDF) using the MMT-Magellan Infrared Imager and Spectrometer on the MMT. These new observations cover a field of approximately 230 arcmin2inY,H, andK,and 313 arcmin2inJ. Using Monte Carlo simulations, we estimate a 1σdepth relative to the background sky of (Y, J, H, K) = (23.80, 23.53, 23.13, 23.28) in AB magnitudes for point sources at a 95% completeness level. These observations are part of the ground-based effort to characterize this region of the sky, supplementing space-based data obtained with Chandra, NuSTAR, XMM, AstroSat, Hubble Space Telescope, and JWST. This paper describes the observations and reduction of the NIR imaging and combines these NIR data with archival imaging in the visible, obtained with the Subaru Hyper-Suprime-Cam, to produce a merged catalog of 57,501 sources. The new observations reported here, plus the corresponding multiwavelength catalog, will provide a baseline for time-domain studies of bright sources in the NEP TDF.

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DOI PREFIX: 10.3847
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Journal Name:
The Astrophysical Journal Supplement Series
Medium: X Size: Article No. 21
["Article No. 21"]
Sponsoring Org:
National Science Foundation
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