A search for extragalactic H2O maser emission towards IRAS galaxies II - Discovery of an H2O maser in the Seyfert 1 galaxy NGC 4051
Abstract
Water vapor maser emission in the 616-523 transition towards the narrow-line Seyfert 1 (NLS1) galaxy NGC 4051 has been discovered during an ongoing single-dish extragalactic water maser survey. The Doppler-shifted maser components appear to bracket maser components lying near the systemic velocity of the galaxy symmetrically. The tentative result of a Very Large Array (VLA) snapshot observation is that the masers are confined within 0.1 arcsec (5 pc at a distance D = 9.7 Mpc) of the radio continuum peak seen at 8.4 GHz. The low luminosity of the maser (~2 Lsun) is not typical for masers that coincide with the radio continuum nucleus and appear associated with Active Galactic Nucleus (AGN) activity. A low-luminosity maser in a Type 1 Seyfert nucleus could be explained by a low maser gain resulting from the lower inclination of an obscuring disk around an active nucleus.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.