"Nature" (published in 20220217) Introduction to one week's papers

Compilation | Feng Weiwei

Nature, Volume 602 Issue 7897, 17 February 2022

"Nature" Volume 602 Issue 7897, February 17, 2022

Physics

Thermal imaging of dust hiding the black hole in NGC 1068

Unified model of active galactic nuclei confirmed

Author: Violeta Gámez Rosas, Jacob W. Isbell, Gerard Zins, etc.

Link:

/articles/s41586-021-04311-7

Abstract

Violeta Gamez Rosas of Leiden University in the Netherlands and her collaborators observed the densely obscuring dust surrounding the black hole near the center of the galaxy and confirmed the unified model of active galactic nuclei. The authors reached this conclusion through analysis of high-resolution images of this galaxy, which provide new opportunities to study active galactic nuclei.

Active galactic nuclei are high-energy regions at the centers of some galaxies that are thought to be powered by supermassive black holes. The spectral characteristics of the light emitted by these nuclei are related to the area from which the light is emitted; different spectra can be used to distinguish AGNs into two categories: Type I and Type II objects. But the unified model suggests that this distinction occurs because the view may sometimes be obscured by a ring of dust surrounding and pouring into the central black hole.

The authors' observations support the unified model. They obtained high-resolution images of the prototype galaxy NGC 1068, from which the unified theory was first established. They used an instrument called MATISSE, which combines light from four European Southern Observatory telescopes to get the best view of the AGN. Analysis of these images and radio maps revealed the presence of the ring dust cloud and helped determine its properties, which mostly match Unified Model predictions. The authors also located the black hole's location beneath the dust ring, which also fits the model.