2022ApJ...935...80L

Wide-field Infrared Survey Explorer all-sky survey has discovered a new population of hot dust-obscured galaxies (Hot DOGs), which have been confirmed to be dusty quasars. Previous statistical studies have found significant overdensities of submillimeter and mid-IR-selected galaxies around Hot DOGs, indicating they may reside in dense regions. Here we present the near-infrared (J and K_s bands) observations over a $7\buildrel{\,\prime}\over{.} 5\times 7\buildrel{\,\prime}\over{.} 5$ field centered on a Hot DOG W1835+4355 at z ∼ 2.3 using the wide-field infrared camera on the Palomar 200 inch telescope. We use the color criterion J - K_s > 2.3 for objects with ${K}_{S}\lt 20$, to select distant red galaxies (DRGs). We find a significant excess of number density of DRGs in the W1835+4355 field compared to three control fields, by a factor of about two. The overdensity of red galaxies around W1835+4355 is consistent with the multiwavelength environment of Hot DOGs, suggesting that Hot DOGs may be a good tracer for dense regions at high redshift. We find that W1835+4355 does not reside in the densest region of the dense environment traced by itself. A possible scenario is that W1835+4355 is undergoing a merging process, which lowers the local number density of galaxies in its surrounding region.