학술논문
Little Red Dots: An Abundant Population of Faint Active Galactic Nuclei at z ∼ 5 Revealed by the EIGER and FRESCO JWST Surveys
Document Type
article
Author
Jorryt Matthee; Rohan P. Naidu; Gabriel Brammer; John Chisholm; Anna-Christina Eilers; Andy Goulding; Jenny Greene; Daichi Kashino; Ivo Labbe; Simon J. Lilly; Ruari Mackenzie; Pascal A. Oesch; Andrea Weibel; Stijn Wuyts; Mengyuan Xiao; Rongmon Bordoloi; Rychard Bouwens; Pieter van Dokkum; Garth Illingworth; Ivan Kramarenko; Michael V. Maseda; Charlotte Mason; Romain A. Meyer; Erica J. Nelson; Naveen A. Reddy; Irene Shivaei; Robert A. Simcoe; Minghao Yue
Source
The Astrophysical Journal, Vol 963, Iss 2, p 129 (2024)
Subject
Language
English
ISSN
1538-4357
Abstract
Characterizing the prevalence and properties of faint active galactic nuclei (AGNs) in the early Universe is key for understanding the formation of supermassive black holes (SMBHs) and determining their role in cosmic reionization. We perform a spectroscopic search for broad H α emitters at z ≈ 4–6 using deep JWST/NIRCam imaging and wide field slitless spectroscopy from the EIGER and FRESCO surveys. We identify 20 H α lines at z = 4.2–5.5 that have broad components with line widths from ∼1200–3700 km s ^−1 , contributing ∼30%–90% of the total line flux. We interpret these broad components as being powered by accretion onto SMBHs with implied masses ∼10 ^7–8 M _⊙ . In the UV luminosity range M _UV,AGN+host = −21 to −18, we measure number densities of ≈10 ^−5 cMpc ^−3 . This is an order of magnitude higher than expected from extrapolating quasar UV luminosity functions (LFs). Yet, such AGN are found in only