Water masers in NLS1 galaxies

Abstract

Luminous extragalactic water masers originate in warm and dense gas in the innermost regions of AGN tracing circumnuclear accretion disks, relativistic jets, or nuclear outflows. So far, the majority of water maser sources have been detected in Sy2 galaxies. Among the few exceptions are the water masers hosted by Narrow-Line Seyfert 1 (NLS1) galaxies. We have studied available line and continuum data at radio frequencies of two NLS1 galaxies, NGC 4051 and NGC 5506, where water maser emission has been detected, to investigate the interplay between this peculiar class of AGN and the maser phenomenon. In this talk, we will illustrate the main results of this study in the framework of a possible association of the water maser sources in NLS1 with radio jets, outflows, or accretion disks. Narrow-Line Seyfert 1 Galaxies and their place in the Universe -NLS1, April