Direct Pathway to the Early Supermassive Black Holes: A Red Super-Eddington Quasar in a Massive Starburst Host at z = 7.2

@article{fei2026direct,
  title = {{Direct Pathway to the Early Supermassive Black Holes: A Red Super-Eddington Quasar in a Massive Starburst Host at z = 7.2}},
  author = {Qinyue Fei and Seiji Fujimoto and Gabriel Brammer and Ruancun Li and Luis C. Ho and Volker Bromm and Javier Álvarez-Márquez and Yoshihisa Asada and Guillermo Barro and Luis Colina and Pratika Dayal and Steven L. Finkelstein and Johan P. U. Fynbo and Michele Ginolfi and Kohei Inayoshi and Vasily Kokorev and Gene C. K. Leung and Jorryt Matthee and Romain A. Meyer and Rohan P. Naidu and Masafusa Onoue and Pablo G. Pérez-González and Charles L. Steinhardt and Francesco Valentino and Fabian Walter and Mengyuan Xiao and Haowen Zhang},
  journal = {The Astrophysical Journal},
  year = {2026},
  month = oct,
  doi = {10.3847/1538-4357/aea07b},
  url = {https://iopscience.iop.org/article/10.3847/1538-4357/aea07b},
  note = {CC BY 4.0},
}

TY  - JOUR
TI  - Direct Pathway to the Early Supermassive Black Holes: A Red Super-Eddington Quasar in a Massive Starburst Host at z = 7.2
AU  - Qinyue Fei
AU  - Seiji Fujimoto
AU  - Gabriel Brammer
AU  - Ruancun Li
AU  - Luis C. Ho
AU  - Volker Bromm
AU  - Javier Álvarez-Márquez
AU  - Yoshihisa Asada
AU  - Guillermo Barro
AU  - Luis Colina
AU  - Pratika Dayal
AU  - Steven L. Finkelstein
AU  - Johan P. U. Fynbo
AU  - Michele Ginolfi
AU  - Kohei Inayoshi
AU  - Vasily Kokorev
AU  - Gene C. K. Leung
AU  - Jorryt Matthee
AU  - Romain A. Meyer
AU  - Rohan P. Naidu
AU  - Masafusa Onoue
AU  - Pablo G. Pérez-González
AU  - Charles L. Steinhardt
AU  - Francesco Valentino
AU  - Fabian Walter
AU  - Mengyuan Xiao
AU  - Haowen Zhang
PY  - 2026
DA  - 2026/10/09
JO  - The Astrophysical Journal
DO  - 10.3847/1538-4357/aea07b
UR  - https://iopscience.iop.org/article/10.3847/1538-4357/aea07b
AB  - We present a panchromatic optical-millimeter characterization of GNz7q, a recently identified X-ray-weak, rapidly growing red quasar embedded within a dusty starburst galaxy at z = 7.1899, using the full suite of JWST/NIRCam, NIRSpec, Mid-Infrared Instrument (MIRI), and archival NOEMA observations. Our deep NIRSpec/G395M spectroscopy reveals unambiguous broad Balmer emission (FWHM = 2221 ± 20 km s ⁻¹ ), confirming a super-Eddington accreting black hole (BH) ( λ Edd = 2.7 ± 0.4) with a mass of log ( M BH / M ⊙ ) = 7.55 ± 0.34 , using accretion-rate-corrected BH mass estimators. After subtracting the point source, we robustly detect stellar emission from the host galaxy across multiple NIRCam and MIRI filters. Our joint morphological-spectral analysis yields a stellar mass of log ( M * / M ⊙ ) = 10.5 ± 0.4 and an intense star formation rate of SFR = 330 ± 97 M ⊙ yr ⁻¹ , confirming the host as a massive, dusty starburst galaxy. We find that GNz7q lies on the local M BH – M * relation ( M BH / M * ≃ 0.001) and is well positioned to evolve into the locus of massive Sloan Digital Sky Survey (SDSS) quasars with log ( M BH / M ⊙ ) ≈ 9 and M * ≈ 10 ¹¹ M ⊙ at z ∼ 6, owing to its remarkably rapid growth in both the BH and its host galaxy. This stands in stark contrast to many recently reported JWST active galactic nucleus populations at similar redshifts, including the little red dots, whose weak or undetected star formation makes it difficult for them to grow into the massive galaxies hosting SDSS-like quasars. These results suggest that GNz7q marks a rare, pivotal phase of early BH–galaxy coevolution, plausibly providing a crucial direct pathway to the supermassive BH systems within the first billion years of the Universe.
SN  - 0004-637X
SN  - 1538-4357
ER  -