Steep Balmer decrement in weak AGNs may be not caused by dust extinction: clues from low-luminosity AGNs and changing-look AGNs

Jiancheng Wu, Qingwen Wu, Hanrui Xue +2

The hydrogen Balmer decrement (e.g., $\mathrm{H}\alpha /H\beta$) is widely adopted as an indicator of the internal reddening of active galactic nuclei (AGNs). This is challenged by some low-lumin…