Physics Commons^™

The Flaring H2o Megamaser And Compact Radio Source In Markarian 348, A. B. Peck, C. Henkel, J. S. Ulvestad, A. Brunthaler, H. Falcke, Moshe Elitzur, K. M. Menten, J. F. Gallimore

Physics and Astronomy Faculty Publications

We report on single-dish monitoring and extremely high angular resolution observations of the flaring H₂O megamaser in the Seyfert 2 galaxy Mrk 348. The H₂O line is redshifted by ~130 km s^-1 with respect to the systemic velocity, is very broad, with an FWHM of 130 km s^-1, and has no detectable high-velocity components within 1500 km s^-1 on either side of the strong line. Monitoring observations made with the Effelsberg 100 m telescope show that the maser varies significantly on timescales as short as 1 day and that the integrated line …