We report the discovery of an accreting supermassive black hole at
Using spatially resolved H
- NSF-PAR ID:
- 10371673
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 937
- Issue:
- 1
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 16
- Size(s):
- ["Article No. 16"]
- Sponsoring Org:
- National Science Foundation
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Abstract z = 8.679. This galaxy, denoted here as CEERS_1019, was previously discovered as a Lyα -break galaxy by Hubble with a Lyα redshift from Keck. As part of the Cosmic Evolution Early Release Science (CEERS) survey, we have observed this source with JWST/NIRSpec, MIRI, NIRCam, and NIRCam/WFSS and uncovered a plethora of emission lines. The Hβ line is best fit by a narrow plus a broad component, where the latter is measured at 2.5σ with an FWHM ∼1200 km s−1. We conclude this originates in the broadline region of an active galactic nucleus (AGN). This is supported by the presence of weak high-ionization lines (N V, N IV], and C III]), as well as a spatial point-source component. The implied mass of the black hole (BH) is log (M BH/M ⊙) = 6.95 ± 0.37, and we estimate that it is accreting at 1.2 ± 0.5 times the Eddington limit. The 1–8μ m photometric spectral energy distribution shows a continuum dominated by starlight and constrains the host galaxy to be massive (log M/M⊙∼9.5) and highly star-forming (star formation rate, or SFR ∼ 30 M⊙yr−1; log sSFR ∼ − 7.9 yr−1). The line ratios show that the gas is metal-poor (Z /Z ⊙∼ 0.1), dense (n e ∼ 103cm−3), and highly ionized (logU ∼ − 2.1). We use this present highest-redshift AGN discovery to place constraints on BH seeding models and find that a combination of either super-Eddington accretion from stellar seeds or Eddington accretion from very massive BH seeds is required to form this object. -
Abstract We present a Keck/MOSFIRE rest-optical composite spectrum of 16 typical gravitationally lensed star-forming dwarf galaxies at 1.7 ≲
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