In the unified model of active galactic nuclei, the broad line region in an active galactic nucleus is
A)composed of clouds of gas and stars moving at very high orbital velocities near a supermassive black hole.
B)composed of a supermassive black hole surrounded by empty space.
C)responsible for producing the bright continuous radiation from within the event horizon.
D)responsible for the narrow absorption lines seen in Type 2 Seyfert galaxies.
E)located far from the core beyond the disk of stars of the galaxy.

Question

Quizplus · Accepted Answer

The unified model of active galactic nuclei proposes that the broad line region in an AGN is composed of clouds of gas and stars moving at very high orbital velocities near a supermassive black hole. These clouds emit broad emission lines due to their motion and heating by radiation from the accretion disk surrounding the black hole. The unified model suggests that the differences in observed properties of AGNs, such as the presence or absence of broad emission lines, are due to differences in our line of sight to the central regions of the AGN.

In the Unified Model of Active Galactic Nuclei, the Broad