Rapidly growing black hole challenges super-Eddington accretion models.

Researchers report a quasar, ID830 at z = 3.4351, accreting around 15 times the Eddington limit while showing unusually strong X-ray and radio emission; this combination is unexpected under standard super-Eddington scenarios.

Astronomers report a quasar, ID830, that appears to be growing far faster than standard models predict. The object is at redshift z = 3.4351, roughly 1.5 billion years after the Big Bang, and was identified in the eROSITA Final Equatorial Depth Survey (eFEDS). The team finds the quasar is accreting at nearly 15 times the Eddington limit while producing strong X-ray and radio emission. The discovery is published in The Astrophysical Journal with lead author Sakiki Obuchi. Key findings: - The source is eFEDS J084222.9+001000 (ID830), reported as the most X-ray luminous radio-loud quasar in the eFEDS field. - It lies at z = 3.4351, corresponding to about 1.5 billion years after the Big Bang. - The authors estimate an accretion rate near 15 times the Eddington limit, a regime where radiation is expected to be trapped and reduce outward emission. - Despite that expectation, ID830 shows unusually strong X-ray and radio output; the team notes jet-linked X-ray components as one possible origin. - The researchers propose ID830 may be in a short-lived transitional phase following a burst of accretion, and they highlight potential implications for rapid black hole growth and jet-driven feedback on host galaxies. Summary: The observation challenges simple super-Eddington interpretations because ID830 combines a very high accretion rate with strong X-ray and radio emission. The authors suggest jet-linked emission or a brief post-burst transitional phase as possible explanations. They report plans to investigate what powers the emissions and to search survey data for similar objects to test these ideas.