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Dense Plasma Torus in the GPS Galaxy NGC 1052

Seiji Kameno·Makoto Inoue·Kiyoaki Wajima·Satoko Sawada-Satoh·Zhi-Qiang Shen
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Abstract

We report results from nearly simultaneous pentachromatic VLBI observations towa rds a nearby GPS galaxy NGC 1052. The observations at 1.6 and 4.8 GHz with VSOP, and at 2.3, 8.4, and 15.4 GHz wit h VLBA, provide linear resolutions of $\sim 0.1$ pc. Convex spectra of a double-sided jet imply that synchrotron emission is obscured through foreground cold dense plasma, in terms of free--free absorption (FFA). We found a central condensation of the plasma which covers about 0.1 pc and 1 pc of the approaching and receding jets, respectively. A simple model with a geometrically thick plasma torus perpendicular to the jets is established to explain the asymmetric distribution of FFA opacities.

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Seiji Kameno, Makoto Inoue, Kiyoaki Wajima, Satoko Sawada-Satoh, Zhi-Qiang Shen. 2002-10-21. Dense Plasma Torus in the GPS Galaxy NGC 1052. https://doi.org/10.1071/as03003

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