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We present a sample of 341 "little red dots" (LRDs) spanning the redshift range z2-11 using data from the CEERS, PRIMER, JADES, UNCOVER and NGDEEP surveys. These sources are likely heavily-reddened AGN that trace a previously-hidden phase of dust-obscured black hole growth in the early Universe. Unlike past use of color indices to identify LRDs, we employ continuum slope fitting using shifting bandpasses to sample the same rest-frame emission blueward and redward of the Balmer break. This approach allows us to identify LRDs over a wider redshift range and is less susceptible to contamination from galaxies with strong breaks that otherwise lack a rising red continuum. The redshift distribution of our sample increases at z<8 and then undergoes a rapid decline at z4. 5, which may tie the emergence, and obscuration, of these sources to the inside-out growth that galaxies experience during this epoch. We find that LRDs are 2-3 dex more numerous than bright quasars at z5-7, but their number density is only 0. 6-1 dex higher than X-ray and UV selected AGN at these redshifts. Within our sample, we have identified the first X-ray detected LRDs at z=3. 1 and z=4. 66. An X-ray spectral analysis confirms that these AGN are moderately obscured with \, (N ₇/ cm^2) of 23. 3^+0. 4-₁. ₃ and 22. 72^+0. 13-₀. ₁₆. Our analysis reveals that reddened AGN emission dominates their rest-optical light, while the rest-UV originates from their host galaxies. We also present NIRSpec follow-up spectroscopy of 17 LRDs that show broad emission lines consistent with AGN activity. The confirmed AGN fraction of our sample is 71\% for sources with F444W<26. 5. In addition, we find three LRDs with narrow blue-shifted Balmer absorption features in their spectra, suggesting an outflow of high-density, low ionization gas from near the central engine of these faint, red AGN.
Kocevski et al. (Thu,) studied this question.