JWST and ALMA reveal a dusty, rapidly growing black hole in the early universe

A new study utilizing the James Webb Space Telescope (JWST) and the Atacama Large Millimeter/submillimeter Array (ALMA) has identified a dust-reddened quasar from the universe’s first billion years. As reported by Phys.org, the object, designated J1440+0019, is located at a redshift of 6.5488 and contains a supermassive black hole with a mass of approximately 1.1 billion suns. The research, led by Daming Yang of the Leiden Observatory, was posted to the arXiv preprint server on October 9.

The findings provide critical data regarding the epoch of cosmic reionization, which occurred between 600 million and one billion years after the Big Bang (redshifts 6 to 8). During this period, ionizing UV radiation from early stars and galaxies transformed neutral hydrogen gas into an ionized state. While most quasars from this era are found via bright ultraviolet light, J1440+0019 was identified as a red type-1 quasar, meaning its nucleus is viewed directly through moderate dust extinction.

The research team combined JWST NIRSpec spectroscopy of the quasar's core with ALMA observations of the host galaxy’s cold gas and dust. The spectrum revealed prominent emission lines and obscuration consistent with dust reddening. Furthermore, the researchers detected high-ionization absorption systems that are blueshifted, indicating nuclear outflows moving at speeds up to 3,600 kilometers per second. This identifies J1440+0019 as having one of the brightest ionized carbon emission sources known at redshifts above 6.

Observations from ALMA showed that the host galaxy contains an estimated 400 million solar masses of dust and exhibits a star-formation rate with an upper limit of 1,330 sun-like stars per year. Despite the massive dust reservoir, the quasar is accreting material rapidly, radiating at approximately 80% of its Eddington luminosity. The team noted that primary tracers were extracted using only 5.5 minutes of ALMA observing time, suggesting an efficient method for identifying similar systems.

What to watch: Future spectroscopic follow-ups of reddened-quasar candidates identified through the team's efficient ALMA-based survey method.

Editor's note: The draft effectively synthesizes the scientific findings, technical details, and context provided in the source material.