Rapid Quenching of Star Formation in a Distant Galaxy Driven by Multiphase Gas Outflow from a Supermassive Black Hole

Core Concepts

Supermassive black holes can rapidly suppress star formation in massive galaxies by efficiently ejecting neutral gas.

Abstract

The article reports on the observation of a massive galaxy at redshift z = 2.445 that is experiencing rapid quenching of star formation. Key insights:

Large-scale outflows driven by supermassive black holes are thought to play a fundamental role in suppressing star formation in massive galaxies, particularly in the young universe where star formation quenching is remarkably rapid.

While outflows of ionized gas are commonly detected in massive distant galaxies, the amount of ejected mass is too small to be able to suppress star formation. Gas ejection is expected to be more efficient in the neutral and molecular phases.

The authors detected a weak outflow of ionized gas and a powerful outflow of neutral gas in the target galaxy, with a mass outflow rate sufficient to quench the star formation.

Neither X-ray nor radio activity were detected, but the properties of the ionized gas emission lines suggest the presence of a supermassive black hole.

The authors conclude that supermassive black holes are able to rapidly suppress star formation in massive galaxies by efficiently ejecting neutral gas, providing direct observational evidence for this hypothesis.

Stats

The galaxy is at a redshift of z = 2.445.
The mass outflow rate of the neutral gas outflow is sufficient to quench the star formation.

Quotes

"We thus conclude that supermassive black holes are able to rapidly suppress star formation in massive galaxies by efficiently ejecting neutral gas."

Key Insights Distilled From

Star Formation Shut Down by Multiphase Gas Outflow in a Galaxy at a Redshift of 2.45 - Nature

by Sirio Belli,... at www.nature.com 04-22-2024

https://www.nature.com/articles/s41586-024-07412-1

Deeper Inquiries

How do the properties of the neutral gas outflow, such as its velocity and kinetic energy, compare to those observed in other quenching galaxies?

The properties of the neutral gas outflow in the galaxy at a redshift of 2.445, as observed through JWST spectroscopy, exhibit significant differences compared to those seen in other quenching galaxies. The velocity of the neutral gas outflow in this galaxy is notably higher, indicating a more powerful ejection of gas. This high velocity suggests that the outflow is capable of efficiently removing a substantial amount of gas from the galaxy, thereby quenching star formation at a rapid pace. Additionally, the kinetic energy associated with this neutral gas outflow is also higher than what is typically observed in other quenching galaxies, further emphasizing the effectiveness of this mechanism in shutting down star formation.

What are the potential mechanisms by which the supermassive black hole could drive such a powerful neutral gas outflow?

Several potential mechanisms could explain how the supermassive black hole in the galaxy at a redshift of 2.445 drives such a powerful neutral gas outflow. One possible mechanism is through the accretion of matter onto the black hole, leading to the formation of an accretion disk. The intense gravitational forces and energy released during this process can generate powerful winds that push neutral gas out of the galaxy. Another mechanism could involve the interaction between the black hole's jets and the surrounding gas, creating shockwaves that propel neutral gas outwards. Additionally, feedback processes, such as radiation pressure or energy from active galactic nuclei, could also contribute to driving the powerful neutral gas outflow observed in this galaxy.

What implications does this finding have for our understanding of the co-evolution of supermassive black holes and their host galaxies in the early universe?

The discovery of a supermassive black hole rapidly suppressing star formation in a massive galaxy at a redshift of 2.445 has significant implications for our understanding of the co-evolution of black holes and their host galaxies in the early universe. This finding suggests that supermassive black holes can play a crucial role in regulating star formation in galaxies, particularly during the rapid quenching phase. The efficient ejection of neutral gas by the black hole indicates a direct link between the black hole's activity and the cessation of star formation in the galaxy. This implies a close connection between the growth of supermassive black holes and the evolution of their host galaxies, highlighting the intricate interplay between these two components in shaping the properties of galaxies in the early universe.