James Webb Space Telescope Feed Post
A Census of Photometrically Selected Little Red Dots at 4 < z < 9 in JWST Blank Fields
Selection and analysis of LRD candidates. Top: Sample selection criteria. The left and central panels show modified “red 1” (z?6) and “red 2” (z?6) color-color cuts from Labbé et al. (2023b). The right panel shows the compactness cut of our sample. Selected objects are highlighted as maroon circles, while grayscale hexbins show the full catalog. The compact red sources are clear outliers in color-color-compactness space. Colorbar is shared between all plots. Bottom: An example of best-fit SEDs to the photometry of LRD candidates with the dust-free (blue) and dusty (red) AGN templates (Vanden Berk et al., 2001; Glikman et al., 2006) at representative redshifts of z~6 and z~8. The combined model is shown in black. Detections (>3?s) are shown as red circles, while upper limits (primarily from HST) are shown as downward arrows. On the right of each SED we show 1.''5 color composite cutouts in the short (F115W/F150W/F200W) and long (F277W/F356W/F444W) NIRCam filters.
Abstract: Observations with the James Webb Space Telescope (JWST) have uncovered numerous faint active galactic nuclei (AGN) at z~5 and beyond. These objects are key to our understanding of the formation of supermassive black holes (SMBHs), their co-evolution with host galaxies, as well as the role of AGN in cosmic reionization. Using photometric colors and size measurements, we perform a search for compact red objects in an array of blank deep JWST/NIRCam fields totaling ~640 arcmin2. Our careful selection yields 260 reddened AGN candidates at 4
