An X-ray look into the heart of powerful quasars

May 19. (EUROPE PRESS) –

Scientists have observed the X-ray emission from the most luminous quasar seen in the last 9 billion years of cosmic history, known as J1144.

The new perspective sheds light on the inner workings of quasars and how they interact with their surroundings. The research is published in Monthly Notices of the Royal Astronomical Society.

Hosted by a galaxy 9.6 billion light-years from Earth, between the constellations Centaurus and Hydra, J1144 is extremely powerful, shining 100 billion times brighter than the sun. J1144 is much closer to Earth than other sources of the same luminosity, allowing astronomers to obtain information about the black hole that feeds the quasar and the environment around it.

The study was led by Dr. Elias Kammoun, a postdoctoral researcher at the Institute for Research in Astrophysics and Planetology (IRAP), and Zsofi Igo, a PhD candidate at the Max Planck Institute for Extraterrestrial Physics (MPE).

Quasars are among the brightest and most distant objects in the known universe, fueled by gas falling into a supermassive black hole. They can be described as very high luminosity active galactic nuclei (AGNs) that emit large amounts of electromagnetic radiation observable at radio, infrared, visible, ultraviolet, and X-ray wavelengths. J1144 was initially observed at visible wavelengths in 2022 by SkyMapper Southern Survey (SMSS).

For this study, the researchers combined observations from several space-based observatories: the eROSITA instrument aboard the Spectrum-Roentgen-Gamma (SRG) observatory, the ESA XMM-Newton observatory, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) and the observatory NASA’s Neil Gehrells.

The team used the data from the four observatories to measure the temperature of the X-rays emitted by the quasar. They found that this temperature is around 350 million Kelvin, more than 60,000 times the temperature at the surface of the sun. The team also found that the mass of the black hole at the center of the quasar is around 10 billion times the mass of the sun, and the rate at which it grows is on the order of 100 solar masses per year.

The X-ray light from this source varied on a time scale of a few days, which is not usually seen in quasars with black holes as large as the one residing in J1144. The typical time scale of variability for a black hole of this size would be on the order of months or even years. The observations also showed that while some of the gas is swallowed by the black hole, some of the gas is expelled in the form of extremely powerful winds, injecting large amounts of energy into the host galaxy.

Dr. Kammoun, lead author of the paper, says: “We were very surprised that no previous X-ray observatory has observed this source. despite his extreme power.”

add it’s a statement: “Similar quasars generally are at much greater distances, so they appear much fainter, and we see them as they were when the Universe was only 2-3 billion years old. J1144 is a very rare source, as it is very bright and much closer to Earth (although still a long way away!), giving us a unique insight into what these powerful quasars look like.”

“A new monitoring campaign for this source will begin in June this year, which may reveal more surprises from this unique source.”