Search for Free-Free Absorption Cutoffs from Tori in Three Type 2 Active Galactic Nuclei
نویسندگان
چکیده
We have observed three Type 2 radio loud active galactic nuclei using the VLBA at five frequencies between 1.6 GHz and 15 GHz, in a search for the free-free absorption cutoff predicted by some models for optically-obscuring dusty molecular tori. We find no evidence for sharp cutoffs toward low frequencies in any of the sources. However, one source, OW637, has VLBI components which are steeply falling toward high frequencies (Sν ∝ ν ). Subject headings: Galaxies: Active
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تاریخ انتشار 1997