New research has provided insights into how supermassive black holes impact the distribution of chemicals within galaxies. Supermassive black holes have long been known to exert a significant influence on the galaxies surrounding them. As these black holes feed on surrounding matter, they emit bright electromagnetic radiation that can outshine the light from all the stars in their galaxy. This feeding process also generates jets of matter that shoot out from the black hole at nearly the speed of light.
These phenomena collectively form what is known as an active galactic nucleus (AGN). The AGN heats gas and dust, pushing star-forming matter away from the region and potentially limiting the growth of the galaxy. However, the distribution of chemicals within galaxies, influenced by AGNs and their black hole engines, has remained less understood.
In a recent study, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to examine the AGN of the galaxy NGC 1068, also known as Messier 77 or the “Squid Galaxy.” They focused on analyzing the distribution of chemicals surrounding the bright center of this barred spiral galaxy. The AGN in this galaxy is surrounded by a dense ring of dust called a circumnuclear disk and a region of intense star formation known as the starburst ring.
Using ALMA’s impressive spatial resolution and a new machine learning technique, the researchers successfully mapped the distribution of 23 different molecules within the galaxy. By analyzing the absorption of light at characteristic wavelengths by these molecules, the team could identify their chemical composition.
The researchers discovered that hydrogen cyanide isotopes were concentrated in the central region of the AGN, while cyanide radicals were found both at the active center of the galaxy and in jets extending from the supermassive black hole. However, carbon monoxide isotopes, which are common in galaxies, were notably absent in the central region.
These findings provide clear evidence that supermassive black holes not only affect the overall structure of galaxies but also impact their chemical composition. The study also revealed surprises, with the team realizing that high-energy X-rays from the AGN had a lesser impact on chemical distribution than anticipated.
The research has important implications for understanding the evolution of galaxies and highlights the effectiveness of employing line surveys in galaxy chemistry research.
Sumber: The Astrophysical Journal