Unlocking the Secrets of Cosmic Monsters: VERA Telescope Network Reveals the Surprising Surroundings of Rapidly Growing Black Holes

 

A rapidly growing supermassive black hole emits jets and surrounding outflows. When radio waves are released near the black hole, their polarization plane rotates as they pass through the magnetized gas around it. Image credit: NAOJ.

 

 

A team of international astronomers, led by Mieko Takamura, a graduate student at the University of Tokyo, has made significant progress in understanding the growth of young supermassive black holes in Narrow-line Seyfert 1 (NLS1) galaxies. They used the VERA network of radio telescopes, operated by the National Astronomical Observatory of Japan (NAOJ), to gain new insights into these celestial entities.

Almost every active galaxy is believed to have a supermassive black hole at its core, ranging in mass from millions to billions of times that of the Sun. However, how these black holes grow to such enormous sizes remains an open question.

The team focused on NLS1 galaxies, which are suspected to contain small but rapidly growing massive black holes, providing an opportunity to study an early evolutionary stage of these cosmic objects.

To better understand the immediate surroundings of these unique black holes, the team observed the cores of six nearby active NLS1 galaxies using VERA, a powerful radio telescope network capable of detecting faint polarized radio waves from the galaxies' cores with exceptional precision.

When radio waves are emitted near supermassive black holes, they become polarized. As these polarized waves pass through the magnetized gas surrounding the black hole, they undergo a rotation known as Faraday rotation. This rotation is influenced by the density of the gas and the strength of the magnetic field in the surrounding medium, providing valuable information about the black hole's environment.

The new data from VERA revealed significantly more Faraday rotation in NLS1 galaxies compared to measurements obtained from older, more massive black holes. This suggests the presence of abundant gas in the nuclear regions of these galaxies, which facilitates the rapid growth of the central black holes.

In simpler terms, the astronomers used advanced radio telescope technology to study young supermassive black holes in certain galaxies. They found that these black holes are surrounded by a lot of gas, which helps them grow quickly. The results were published in the Astrophysical Journal as Takamura et al. "Probing the heart of active narrow-line Seyfert 1 galaxies with VERA wideband polarimetry."

Reference:Probing the Heart of Active Narrow-line Seyfert 1 Galaxies with VERA Wideband Polarimetry

Mieko Takamura, Kazuhiro Hada, Mareki Honma, Tomoaki Oyama, Aya Yamauchi, Syunsaku Suzuki, Yoshiaki Hagiwara, Monica Orienti, Filippo D'Ammando, Jongho Park, Minchul Kam, and Akihiro Doi.

Published 2023 July 18 • © 2023. The Author(s). Published by the American Astronomical Society.
The Astrophysical Journal, Volume 952, Number 1Citation Mieko Takamura et al 2023 ApJ 952 47DOI 10.3847/1538-4357/acd9a8