Astonishing Discovery in Quasar Radiation

In a remarkable discovery based on a theory proposed by Albert Einstein over a century ago, astronomers have identified emissions from the core of a quasar, where a supermassive black hole resides. This discovery was led by a team under the guidance of Mateusz Rebak from Leiden University, who developed this finding while searching for cold gas in the galaxy RXJ1131-1231.

The Role of Gravitational Lensing in the Discovery

The galaxy RXJ1131-1231 is a popular target for astronomers due to the gravitational lensing effect predicted by Einstein’s general theory of relativity in 1915. This effect occurs when a massive object sits between Earth and a background source, such as the quasar in RXJ1131-1231, causing a distortion in spacetime and the path of light.

This distortion is known as macrolensing, where the background source appears three times larger than its natural size. There is also a less extreme form known as microlensing, where the intervening object is less massive than a galaxy, and this form played a pivotal role in this study.

Techniques Used in the Study

The team used the Atacama Large Millimeter/submillimeter Array (ALMA) in the Atacama Desert in northern Chile to study RXJ1131-1231. They observed that the three images of the galaxy changed in brightness independently, which was strong evidence of the presence of microlensing.

According to Rebak, this independent change in brightness reflects the presence of a star between the foreground galaxy and the observer, prompting them to delve deeper into the research. This dual lensing effect, likened to placing two magnifiers over each other, allowed them to see details previously hidden from view.

Intriguing Results

Upon revisiting RXJ1131-1231 in 2020, the team noticed illuminated periods in the quasar over several years. However, the most intriguing aspect was the emission of millimeter-wavelength radiation, which is unusual as this type of radiation typically emanates from calm gases and materials.

The team believes these emissions indicate the presence of a hot, donut-shaped magnetic halo around the supermassive black hole in the quasar.

Conclusion

This research marks an advanced step in the study of microlensing, as the team was able to study millimeter radiation using this technique for the first time. The team plans to continue their study using the Chandra X-ray Observatory to determine the temperature and strength of magnetic fields near supermassive black holes. These studies may help build a better model for understanding how supermassive black holes influence the surrounding galaxies.