Evidence of Supermassive Black Holes in Narrow Emission Line Galaxies

TL;DR

This study provides new evidence for supermassive black holes in narrow emission-line galaxies by analyzing their luminosity relations and mass concentration, suggesting an evolutionary link among different AGN types.

Contribution

It introduces two novel, unambiguous indicators of supermassive black holes in narrow emission-line galaxies based on luminosity relations and mass concentration measurements.

Findings

Seyfert 2 galaxies and LINERs follow the same power law in luminosity relations.

Both galaxy types show high central mass concentration independent of morphology.

Gas kinetic energy in AGNs is likely gravitational in origin.

Abstract

A sample of 229618 narrow emission-line galaxies is used to establish two new unambiguous type of evidence for supermassive black holes at the center of their nuclei: 1) the Seyfert 2 galaxies and LINERs follow the same characteristic power law relating the luminosity of ionized flux with that of the continuum; 2) both show the highest concentration of mass at their center, independent of the morphology of the galaxy, consistent with higher binding energies. The Full Width at Half Maximum is shown to be related with the mass concentration, suggesting that the kinetic energy of the gas in AGNs has a gravitational origin. Within the standard accretion model, the Transition-type Objects, Seyfert 2 galaxies and LINERs represent AGNs forming supermassive black holes on different mass-scales, or they could be related through an evolutionary process, the LINERs representing the end product of this evolution.