Scintillation in the Circinus Galaxy water megamasers

Abstract

We present observations of the 22 GHz water vapor megamasers in the Circinus galaxy made with the Tidbinbilla 70m telescope. These observations confirm the rapid variability seen earlier by Greenhill et al (1997). We show that this rapid variability can be explained by interstellar scintillation, based on what is now known of the interstellar scintillation seen in a significant number of flat spectrum AGN. The observed variability cannot be fully described by a simple model of either weak or diffractive scintillation.

arXiv comment10 pages, 5 figures. AJ accepted

References in corpus (13)

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• Interstellar scintillation as the origin of rapid radio variability in the quasar J1819+3845
• Interstellar Scintillation of the Polarized Flux Density in Quasar, PKS 0405-385
• Annual modulation in the scattering of J1819+3845: peculiar plasma velocity and anisotropy
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• Microarcsecond Radio Imaging using Earth Orbit Synthesis

Cited by in corpus (6)

• Short-period variability in the Class II methanol maser source G12.89+0.49 (IRAS 18089-1732)
• The Megamaser Cosmology Project. VII. Investigating disk physics using spectral monitoring observations
• Green Bank Telescope observations of the water masers of NGC 3079: accretion disk magnetic field and maser scintillation
• Submillimeter H2O Maser in Circinus Galaxy - A New Probe for the Circumnuclear Region of Active Galactic Nuclei
• Performing a stellar autopsy using the radio-bright remnant of SN 1996cr
• Second Epoch ALMA Observations of 321 GHz Water Maser Emission in NGC 4945 and the Circinus Galaxy