An X-ray Bright Nucleus in the Low Surface Brightness Galaxy UGC 6614

TL;DR

This study reveals that the low surface brightness galaxy UGC 6614 hosts an active galactic nucleus with X-ray properties similar to Seyfert I AGNs, indicating the presence of a central black hole despite low star formation.

Contribution

First detailed X-ray analysis of the nuclear region in the LSB galaxy UGC 6614, showing it harbors an AGN with Seyfert I-like properties.

Findings

X-ray luminosity of ~1.1 x 10^{42} erg/s

Black hole mass estimated at ~1.2 x 10^{5} solar masses

X-ray spectral properties similar to Seyfert I AGNs

Abstract

We report a study of the X-ray emission from the nuclear region of the low surface brightness (LSB) galaxy UGC 6614. Very little is known about the central objects in LSB galaxies especially their X-ray properties and X-ray spectra. In this study we have used XMM-Newton archival data to study the characteristics of the X-ray spectrum and the X-ray flux variability of the AGN in the LSB galaxy UGC 6614. The nucleus of UGC 6614 is very bright in X-ray emission with an absorption corrected 0.2-10.0 keV luminosity of ~1.1 x 10^{42} erg s^{-1}. The X-ray spectrum is found to be power-law type with a moderate column density. A short time scale of intensity variation and large X-ray flux is indicative of the presence of a black hole at the centre of this galaxy. Using the method of excess variance, we have determined the black hole mass to be ~0.12 x 10^{6} solar mass. The X-ray spectral properties are similar to that of the Seyfert I type AGNs. Our study thus demonstrates that although LSB galaxies are poor in star formation, they may harbour AGNs with X-ray properties comparable to that seen in more luminous spiral galaxies.